[feat] Support Colocated Weight Sync via CUDA IPC for vime - #22
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This pull request introduces support for updating colocated vLLM rollout engines using CUDA IPC (Ray mode), primarily through the new UpdateVLLMWeightFromTensor class and associated vLLM engine configurations. The implementation handles both colocated IPC transfers and distributed NCCL fallbacks, supported by a new worker extension for internal patching. Feedback focuses on performance optimizations, specifically recommending batching engine handles in trainer_send_weights to minimize synchronization overhead and parallelizing remote initialization calls. Other suggestions include removing redundant environment variable settings and cleaning up debug code.
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If we only call start_weight_update / finish_weight_update from rank 0 and do not barrier after each HF chunk, faster ranks can finish an engine while slower ranks are still sending update_weights, which triggers RuntimeError: start_weight_update must be called before update_weights (HTTP 500) on later training steps. |
| # engines (not per update call). | ||
| self._ipc_initialized: bool = False | ||
| # vLLM IPC handle payloads may use cloudpickle on the Ray/HTTP bridge. | ||
| os.environ.setdefault("VLLM_ALLOW_INSECURE_SERIALIZATION", "1") |
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| os.environ.setdefault("VLLM_ALLOW_INSECURE_SERIALIZATION", "1") | |
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it's already set in slime/backends/vllm_utils/vllm_engine.py when colocate=True
| # engines (not per update call). | ||
| self._ipc_initialized: bool = False | ||
| # vLLM IPC handle payloads may use cloudpickle on the Ray/HTTP bridge. | ||
| os.environ.setdefault("VLLM_ALLOW_INSECURE_SERIALIZATION", "1") |
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it's already set in slime/backends/vllm_utils/vllm_engine.py when colocate=True
| trainer_args=trainer_args, | ||
| ) | ||
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| if self._distributed_engines and self._is_distributed_src_rank: |
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I think it's weird to put distributed related code in ipc file, I think it's the legacy design from slime. This case does exist, do you think it's better to move the code to distributed files?
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I think we should keep it, it's the case that run muti node but within 1 node the weight sync can still be colocated
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But I thought we were talking about a case with both colocate and distributed elements. Wouldn't it be better to separate the distributed code into its own file rather than mixing everything together, and then simply invoke it here?
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Yes, it's the case of mixing colocated and distributed where weight within same node will be send and update first, then weight is send to distributed node.
But the problem is that slime will only use 1 mode either non-colocated and colocated, where non-colocated can handle this case smoothly and for colocated mode, it'll need to invoke both kind of code
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Why it would need to invoke both?
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Why it would need to invoke both?
I believe it's for multi nodes training but we havent test it yet
Brings in vLLMColocateWorkerExtension + IPC weight-transfer-config backend + full start/finish_weight_update colocate bracket. Supersedes the session-bracket-only fix in b59d4d8 (kept locally for history; the PR #22 path is the load-bearing one for actual colocate IPC). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> # Conflicts: # requirements.txt # slime/backends/megatron_utils/update_weight/update_weight_from_tensor.py # slime/backends/vllm_utils/vllm_engine.py
…T_CONFIG_YAML Round-2 rename sweep after PR #18 (and the earlier `7aead3d` round): Docs: docs/{en,zh}/advanced/sglang-config.md → vllm-config.md (git mv) docs/_static/image/sglang_config.png → vllm_config.png (regenerated: redrawn with matplotlib so the three embedded labels — "data generation with arbitary sglang deployment", and "sglang router" twice — are now "data generation with arbitrary vllm deployment" and "vllm router"; "arbitary" typo also fixed) Update all references in docs/{en,zh}/index.rst, usage.md, megatron-config.md, zh/advanced/slime_vllm_backend_design_v1.md. Inside vllm-config.md: --sglang-config→--vllm-config, YAML key sglang:→vllm:, args.sglang_model_routers→args.vllm_model_routers, slime.rollout.sglang_rollout →slime.rollout.vllm_rollout, sglang_basic.yaml→vllm_basic.yaml (and the three other sample filenames), "SGLang ServerArgs"→"vLLM EngineArgs", "SGLang Model Gateway (sgl-router)"→"vllm-router", "python -m sglang.launch_server"→"vllm serve". docs/{en,zh}/advanced/reproducibility.md: # sglang config → # vLLM config --sglang-enable-deterministic-inference → --vllm-enable-deterministic-inference --sglang-attention-backend flashinfer → --vllm-attention-backend flashinfer docs/en/blogs/introducing_slime.md: "slime exclusively integrates SGLang" → "slime/vime exclusively integrates vLLM". (Same edit in zh blog.) Tests: 4 files (test_qwen2.5_0.5B_vllm_config{,_distributed}.py, test_vllm_config_mixed_offload{,_ft}.py): ROLLOUT_CONFIG_YAML→VLLM_CONFIG_YAML + "Inline rollout config"→"Inline vLLM config". slime/utils/arguments.py: 10 help strings on top-level rollout flags (--colocate description, --rollout-temperature/top-p/top-k, max-context/prompt/response-len, stop words/token-ids) said "the inference engine" generically — now say "vLLM" to match the vLLM-only state of the repo. slime/backends/megatron_utils/update_weight/update_weight_from_tensor.py: one docstring line "all rollout engines" → "all vLLM engines" (this is the colocate IPC path, vLLM-specific; PR #22 already merged). examples/search-r1/generate_with_search.py: one comment about strict token alignment of "the inference engine" → "vLLM". Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The README B200 paragraph told users to pass `--sglang-mm-attention-backend sdpa` to work around FA3 missing on Blackwell. Two problems: 1. The `--sglang-*` namespace was removed by PR #18, so following this advice now fails at parse_args. 2. The advice is unnecessary for vllm: vllm auto-dispatches the ViT encoder on Blackwell to FA4 (or FA2 fallback) without any user intervention. - vllm/v1/attention/backends/fa_utils.py:77-104 picks fa_version=4 when device_capability.major == 10 and explicitly rejects fa_version=3 on Blackwell with a warning. - vllm/platforms/cuda.py:404-440 (get_vit_attn_backend) iterates [FLASH_ATTN, TRITON_ATTN, TORCH_SDPA, FLASHINFER] and selects the first whose supports_compute_capability accepts (10, 0). That's FLASH_ATTN, which internally uses FA4. Rewrote the paragraph to explain the vllm-native default and document `--vllm-mm-encoder-attn-backend TORCH_SDPA` only as a manual escape hatch. The HF-side `--attn-implementation flash_attention_2` note is kept since it's still relevant when the model is loaded via Hugging Face Transformers. Also adds pr18-post-fix-audit.md cataloging the remaining sglang residue in gcl/clean-sglang at 6abfdbc, separating PR #18 fixes from PR #22 territory. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
PR #22's colocate-IPC weight transfer path calls _apply_monkey_patch_torch_reductions (update_weight_from_tensor.py:247,319), which lazy-imports `monkey_patch_torch_reductions` from `slime.backends.megatron_utils.sglang`. PR #18 deleted that module — the function now lives at `slime.backends.megatron_utils.update_weight.torch_patch` (vendored from sglang's patch_torch utility; same code, new home). On PR #22 standalone this worked because the deletion hasn't landed on main. On `gcl/clean-sglang` (= main + PR #18 + PR #22 merge), the import raises `ModuleNotFoundError: No module named 'slime.backends. megatron_utils.sglang'` the first time the colocate path is hit. This shows up in every smoke test that uses `--colocate` (gb10-smoke reproduces it within ~2 minutes of startup, right after Megatron loads weights and tries to sync to vLLM). Pointed both the production call site (update_weight_from_tensor.py:52) and the test stub (test_update_weight_from_tensor.py:48-50) at the new torch_patch module. The sibling `hf_weight_iterator_direct.py:16` already uses `from .torch_patch import monkey_patch_torch_reductions` post-PR-18, so this just brings the second consumer into line. The PR #22 author cannot land this fix on their own branch because `torch_patch.py` does not exist on `main` yet — the rewire only makes sense in the integrated PR #18 + PR #22 state, which is exactly `gcl/clean-sglang`. Audit §1A in pr18-post-fix-audit.md tracked this. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com>
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Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com>
Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com>
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Hi @knlnguyen1802 — found a test/production drift that should be cleaned up in this PR before merge. What happenedCommit
That's a deliberate design choice — fine on its own. But PR #21 also added two tests in Both set Verification
FixDelete those two test functions (~lines 106–114 and 334–342 of # (PR #21's leader-skip path was removed in commit 47158c1 of this PR;
# vime engines are always single-node per actor, so node_rank is always 0
# and the skip branch was unreachable. Tests for that branch deleted.)That keeps the test surface honest about what production actually does on this branch. (I'd send a small PR against |
Hi , I think it's better if you can do a small PR again this. Thanks |
Two regressions surfaced after PR #18 merged PR #22 (update_weights_tensor) into gcl/clean-sglang: 1. ``slime/backends/vllm_utils/vllm_engine.py`` had duplicate ``def start_weight_update`` / ``def finish_weight_update`` definitions. PR #21 (#f7ac630, "Sync to vLLM 0.21.0") added a leader-aware version at ~line 569/581 with ``_skipped_if_not_leader()`` self-protection. PR #22's #47158c1 commit added its own no-skip version at ~line 820/834 without removing PR #21's. Python class-body semantics shadow the earlier definitions, so the no-skip version was the one running at runtime. The merge artifact didn't cause runtime crashes (vime engines always have ``self.node_rank = 0`` — only assignment in the codebase, line 459), but it left two defensive code paths dead-coded and confused review. Resolution: keep PR #22's design (drop leader-skip path entirely since ``node_rank`` is structurally 0 in current vime), remove the duplicates, and also remove the now-orphan ``_SKIP_NON_LEADER`` constant and ``_skipped_if_not_leader`` method. PR #22 author has been pinged (#22 comment) to also drop the corresponding ``test_*_skipped_when_node_rank_nonzero`` tests on their branch. 2. ``tests/test_update_weight_from_tensor.py::_make_instance`` (added on gcl/pr18-tests-ci via #b6a357a) bypasses ``__init__`` with ``object.__new__`` and hand-sets attributes. It was missing ``obj._ipc_engine = None`` and 12 tests that mutate ``obj._colocated_engines = [...]`` after ``_make_instance`` returned never wired ``_ipc_engine`` either. Production code at ``update_weight_from_tensor.py:237`` gates IPC lifecycle on ``self._ipc_engine is not None`` and the helper sets ``_ipc_engine`` to one designated engine in ``connect_rollout_engines`` — the tests need to replicate that designation. Resolution: add ``obj._ipc_engine = None`` to the ``_make_instance`` base, plus ``obj._ipc_engine = obj._colocated_engines[0] if obj._colocated_engines else None`` at every non-empty ``_colocated_engines`` mutation site (12 occurrences, batch-applied). Updated ``test_multiple_colocated_engines_all_get_lifecycle_calls`` to match production: release/resume/init are fanned out to all engines, but start/finish_weight_update is sent only to the designated ``_ipc_engine`` (PR #22's coordinator-per-rank design). Verified on h200-1 with vime-vllm-cu129-latest image (single GPU, Qwen3-4B compatible): - ``pytest tests/test_update_weight_from_tensor.py``: 29 passed - ``pytest tests/unit/backends/vllm_utils/test_vllm_engine.py``: 26 passed, 2 failed (``test_*_skipped_when_node_rank_nonzero`` — owner-pinged via #22). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Commit 3b12c77 on this branch consolidated start_weight_update / finish_weight_update to PR #22's no-leader-skip version (dropping the PR #21 defensive guard that vime's node_rank=0 architecture never exercises). The two tests below were left behind asserting the now- removed self-skip behavior: - test_start_weight_update_skipped_when_node_rank_nonzero - test_finish_weight_update_skipped_when_node_rank_nonzero Both set node_rank=1 and assert _post_json is never called; after the 3b12c77 dedup, production posts unconditionally (engines are always single-node-per-actor, node_rank is structurally 0), so these tests fail with "should not POST". Their assertion no longer reflects the production contract. Deleting them. The remaining 26 tests in this file still verify the HTTP shapes for /start_weight_update, /finish_weight_update, /update_weights, /sleep, /wake_up, etc. PR #22 author was pinged about this in #22 (comment) but has not acted; doing the cleanup on PR #18 since these tests are unblocking the unit-all batch run. After this commit: pytest tests/unit/backends/vllm_utils/test_vllm_engine.py → 26 passed (was 26 passed, 2 failed) Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
After PR #22 added the colocated CUDA IPC weight sync path, the IPC branch bypasses ``VLLMEngine.update_weights_from_tensor`` entirely (data moves through ``IPCWeightTransferEngine.trainer_send_weights`` directly, not the ``/update_weights`` RPC). That RPC is the normal place where the engine's ``self._weight_version`` gets recorded; the IPC path leaves it at the initial ``None``. The fail mode shows up the first time IPC weight sync runs with ``--ci-test``: ``actor.update_weights`` at slime/backends/megatron_utils/actor.py picks a random rollout engine, calls ``get_weight_version()``, and compares against the trainer-side ``weight_updater.weight_version``. Because the engine's ``_weight_version`` is still ``None``, ``get_weight_version`` falls back to ``GET /v1/models`` and returns the model path string (e.g. ``/root/models/Qwen2.5-0.5B-Instruct``); the updater returns the integer version string (``"1"``, ``"2"``, ...). They never match: RuntimeError: Weight version mismatch! Engine: /root/models/Qwen2.5-0.5B-Instruct, Updater: 1 Reproducer: ``tests/test_qwen2.5_0.5B_short.py`` and ``tests/test_qwen2.5_0.5B_ppo_critic_only_short.py`` once they reach ``update_weights`` — both colocate + IPC, both have ``--ci-test`` set. Thread the version through: - ``VLLMEngine.finish_weight_update(weight_version: str | None = None)`` now sets ``self._weight_version = str(weight_version)`` before issuing the ``POST /finish_weight_update``. - ``UpdateWeightFromTensor.update_weights`` (step 5) passes ``str(self.weight_version)`` when the coordinator rank fires the per-engine ``finish_weight_update`` RPC. Each colocated engine's coordinator rank fires its own ``finish_weight_update``, so every engine ends up with the new version recorded; the distributed path is unchanged. Signed-off-by: aoshen02 <aoshen@inferact.ai>
…ses (#45) After PR #22 added the colocated CUDA IPC weight sync path, the IPC branch bypasses ``VLLMEngine.update_weights_from_tensor`` entirely (data moves through ``IPCWeightTransferEngine.trainer_send_weights`` directly, not the ``/update_weights`` RPC). That RPC is the normal place where the engine's ``self._weight_version`` gets recorded; the IPC path leaves it at the initial ``None``. The fail mode shows up the first time IPC weight sync runs with ``--ci-test``: ``actor.update_weights`` at slime/backends/megatron_utils/actor.py picks a random rollout engine, calls ``get_weight_version()``, and compares against the trainer-side ``weight_updater.weight_version``. Because the engine's ``_weight_version`` is still ``None``, ``get_weight_version`` falls back to ``GET /v1/models`` and returns the model path string (e.g. ``/root/models/Qwen2.5-0.5B-Instruct``); the updater returns the integer version string (``"1"``, ``"2"``, ...). They never match: RuntimeError: Weight version mismatch! Engine: /root/models/Qwen2.5-0.5B-Instruct, Updater: 1 Reproducer: ``tests/test_qwen2.5_0.5B_short.py`` and ``tests/test_qwen2.5_0.5B_ppo_critic_only_short.py`` once they reach ``update_weights`` — both colocate + IPC, both have ``--ci-test`` set. Thread the version through: - ``VLLMEngine.finish_weight_update(weight_version: str | None = None)`` now sets ``self._weight_version = str(weight_version)`` before issuing the ``POST /finish_weight_update``. - ``UpdateWeightFromTensor.update_weights`` (step 5) passes ``str(self.weight_version)`` when the coordinator rank fires the per-engine ``finish_weight_update`` RPC. Each colocated engine's coordinator rank fires its own ``finish_weight_update``, so every engine ends up with the new version recorded; the distributed path is unchanged. Signed-off-by: aoshen02 <aoshen@inferact.ai>
…version-with-data) Background ---------- After PR #22 introduced the colocated CUDA IPC path, vime ended up with three ``update_weights*`` RPC entry points whose ``_weight_version`` bookkeeping was inconsistent: - ``update_weights_from_distributed`` (NCCL path): writes ``_weight_version`` inside the RPC, version travels with data — slime-style. - ``update_weights`` (IPC path, called from ``IPCWeightTransferEngine.trainer_send_weights``): forwarded vLLM's ``IPCWeightTransferUpdateInfo`` to ``/update_weights`` over HTTP but never recorded ``_weight_version`` — vLLM's payload schema does not carry it. - ``update_weights_from_tensor`` (PR #18 legacy entry): kept a SGLang-ish ``serialized_named_tensors`` payload and wrote ``_weight_version``, but had no callers in main. The IPC gap was the root cause of #41-era's "Weight version mismatch! Engine: /root/models/<...>, Updater: N" failure on every colocated test with ``--ci-test`` (fixed in #45 by piggybacking ``weight_version`` onto ``finish_weight_update``). slime's design avoids this entirely: both IPC and distributed call ``engine.update_weights_from_tensor.remote(..., weight_version=N)`` — same RPC name across both repos, with version travelling alongside the data in the same RPC. This PR ------- Rewire vime's IPC path to match slime's interface: 1. ``vllm_engine.update_weights_from_tensor`` is now the IPC entry point. Signature ``(update_info: dict, weight_version: str | None, flush_cache)``; payload carries vLLM's ``IPCWeightTransferUpdateInfo`` (names / dtype_names / shapes / ipc_handles), the trainer constructs it with ``reduce_tensor`` from ``torch.multiprocessing.reductions``. Records ``_weight_version`` only after the POST succeeds — mirrors ``update_weights_from_distributed``'s post-POST ordering so a failed transfer never advances the engine's tracked version. 2. Delete ``vllm_engine.update_weights`` — was the vLLM ``IPCWeightTransferEngine.trainer_send_weights`` entry, no longer used after step 4 below. 3. Delete ``vllm_engine._run_vllm_weight_update`` — dead helper that only ``update_weights_from_tensor``'s old SGLang-ish path called. 4. Revert ``finish_weight_update`` to a stateless POST — ``_weight_version`` now lives in the data-carrying RPC, so the bookend no longer needs to piggyback a kwarg. (Undoes the kwarg added in #45.) 5. Replace ``IPCWeightTransferEngine.trainer_send_weights(...)`` calls in ``_send_hf_chunk_via_ipc`` with direct ``engine.update_weights_from_tensor.remote(update_info=..., weight_version=...)`` for both slot_size paths (slot_size==1 and slot_size>1). vime keeps reusing vLLM's ``reduce_tensor`` for IPC handle creation (via ``_build_ipc_update_info_from_named_tensors``) — only the dispatch is ours — so we don't fork the vLLM IPC protocol, just route through our own RPC surface. Why not just keep #45's piggyback? - #45 worked but coupled version bookkeeping to the lifecycle hook ``finish_weight_update`` instead of the data RPC. The wire shape doesn't match slime's, and a new IPC-style entry point added later would have to remember to also write ``_weight_version`` — exactly the trap PR #22 fell into. Centralising the write inside the data RPC removes the trap. Unit tests ---------- - ``RecordingVLLMEngine`` learns ``update_weights_from_tensor`` so engine RPC call recording stays complete. - Renamed ``test_trainer_send_weights_uses_single_llm_handle_per_rank`` -> ``test_send_via_ipc_dispatches_update_weights_from_tensor_with_version``, asserts the new RPC name + kwargs (``update_info``, ``weight_version``) and that ``finish_weight_update`` is now stateless (no kwargs). - Added ``test_update_weights_from_tensor_posts_ipc_update_info_and_records_version``: asserts ipc_handles get cloudpickle'd into ipc_handles_pickled, metadata fields pass through, ``_weight_version`` advances on POST success. - Added ``test_update_weights_from_tensor_does_not_advance_version_on_failure``: asserts POST failure does not advance ``_weight_version`` (matches the same post-POST ordering review note from #45). Pre-existing test failures in tests/unit/backends/vllm_utils/test_vllm_engine.py (``_weight_transfer_http_timeout``, ``_response_json_or_fallback``, ``server_host``) are unchanged from main — main has 8 failed / 24 passed, this PR has 8 failed / 26 passed (the two added tests). Not in scope here. Signed-off-by: aoshen02 <aoshen@inferact.ai>
Split from PR #18 (gcl/clean-sglang). One of 4 PRs splitting the original PR #18 by content area: docs (#38) / examples (#39) / **tests+CI** / core runtime. 42 files / +~750 / -~700. These are bundled in a single PR because the CI workflows reference test file names by string — splitting them would create a window where either tests are renamed but CI still points at the old names, or vice versa, breaking CI mid-roll. What this PR does: (A) tests/ (38 files): - Mechanical CLI-flag rename: --sglang-* → --vllm-* equivalents in all test scripts (matches the table now used in scripts/ and examples/). - Variable rename: SGLANG_ARGS → VLLM_ARGS where present. - 4 file renames (R086-R091, all >85% similarity): test_qwen2.5_0.5B_opd_sglang.py → test_qwen2.5_0.5B_opd_vllm.py test_qwen2.5_0.5B_sglang_config.py → test_qwen2.5_0.5B_vllm_config.py test_qwen2.5_0.5B_sglang_config_distributed.py → test_qwen2.5_0.5B_vllm_config_distributed.py test_sglang_config_mixed_offload.py → test_vllm_config_mixed_offload.py test_sglang_config_mixed_offload_ft.py → test_vllm_config_mixed_offload_ft.py tests/utils/test_sglang_config.py → tests/utils/test_vllm_config.py - 2 new tests for the IPC weight-transfer path landed in PR #18: tests/test_update_weight_from_tensor.py tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py (These are PR #22 / colocate-IPC test coverage; the production code the slim PR #18 ships will rely on the same code from PR #22.) (B) .github/ (4 files): - workflows/conda-ci.yml: container image lmsysorg/sglang → vime (inferactinc/public:vime-vllm-cu129-latest). - workflows/pr-test.yml + pr-test.yml.j2 (template): * Container images (slimerl/slime[-test]:latest → vime image) on every job that ran on the sglang-era base. * e2e-test-sglang-config job → e2e-test-vllm-config job (renamed label `run-ci-sglang-config` → `run-ci-vllm-config`; matrix `test_file` entries updated to point at the renamed test files in (A)). * e2e-test-megatron + e2e-test-image matrices: `_opd_sglang.py` entries → `_opd_vllm.py`. - ISSUE_TEMPLATE/bug_report.yml: drop the "SGLang version (if relevant):" environment field, add "vLLM version:" and "vllm-router version:" lines. (PR #36 already changed "CUDA/ROCm version" → "CUDA version" earlier; that change is preserved.) Sgl residue intentionally kept (4 hits — all anti-regression assertions that prove sglang code paths are gone, not residual references to bring back): - tests/test_update_weight_from_tensor.py:753 — comment "The vLLM IPC implementation must NOT contain sglang-style Gloo gather code". - tests/unit/backends/vllm_utils/test_arguments.py:233-237 — three assertions that --sglang-router-ip, --sglang-router-port, and sglang_router_ip are NOT present in the argument parser. Tests + CI must land together; splitting them risks a window where the CI matrix references test files by names that don't exist yet (or no longer exist). After this lands, the test_file string in CI matches the test files on disk. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com>
…version-with-data) Background ---------- After PR #22 introduced the colocated CUDA IPC path, vime ended up with three ``update_weights*`` RPC entry points whose ``_weight_version`` bookkeeping was inconsistent: - ``update_weights_from_distributed`` (NCCL path): writes ``_weight_version`` inside the RPC, version travels with data — slime-style. - ``update_weights`` (IPC path, called from ``IPCWeightTransferEngine.trainer_send_weights``): forwarded vLLM's ``IPCWeightTransferUpdateInfo`` to ``/update_weights`` over HTTP but never recorded ``_weight_version`` — vLLM's payload schema does not carry it. - ``update_weights_from_tensor`` (PR #18 legacy entry): kept a SGLang-ish ``serialized_named_tensors`` payload and wrote ``_weight_version``, but had no callers in main. The IPC gap was the root cause of #41-era's "Weight version mismatch! Engine: /root/models/<...>, Updater: N" failure on every colocated test with ``--ci-test`` (fixed in #45 by piggybacking ``weight_version`` onto ``finish_weight_update``). slime's design avoids this entirely: both IPC and distributed call ``engine.update_weights_from_tensor.remote(..., weight_version=N)`` — same RPC name across both repos, with version travelling alongside the data in the same RPC. This PR ------- Rewire vime's IPC path to match slime's interface: 1. ``vllm_engine.update_weights_from_tensor`` is now the IPC entry point. Signature ``(update_info: dict, weight_version: str | None, flush_cache)``; payload carries vLLM's ``IPCWeightTransferUpdateInfo`` (names / dtype_names / shapes / ipc_handles), the trainer constructs it with ``reduce_tensor`` from ``torch.multiprocessing.reductions``. Records ``_weight_version`` only after the POST succeeds — mirrors ``update_weights_from_distributed``'s post-POST ordering so a failed transfer never advances the engine's tracked version. 2. Delete ``vllm_engine.update_weights`` — was the vLLM ``IPCWeightTransferEngine.trainer_send_weights`` entry, no longer used after step 4 below. 3. Delete ``vllm_engine._run_vllm_weight_update`` — dead helper that only ``update_weights_from_tensor``'s old SGLang-ish path called. 4. Revert ``finish_weight_update`` to a stateless POST — ``_weight_version`` now lives in the data-carrying RPC, so the bookend no longer needs to piggyback a kwarg. (Undoes the kwarg added in #45.) 5. Replace ``IPCWeightTransferEngine.trainer_send_weights(...)`` calls in ``_send_hf_chunk_via_ipc`` with direct ``engine.update_weights_from_tensor.remote(update_info=..., weight_version=...)`` for both slot_size paths (slot_size==1 and slot_size>1). vime keeps reusing vLLM's ``reduce_tensor`` for IPC handle creation (via ``_build_ipc_update_info_from_named_tensors``) — only the dispatch is ours — so we don't fork the vLLM IPC protocol, just route through our own RPC surface. Why not just keep #45's piggyback? - #45 worked but coupled version bookkeeping to the lifecycle hook ``finish_weight_update`` instead of the data RPC. The wire shape doesn't match slime's, and a new IPC-style entry point added later would have to remember to also write ``_weight_version`` — exactly the trap PR #22 fell into. Centralising the write inside the data RPC removes the trap. Unit tests ---------- - ``RecordingVLLMEngine`` learns ``update_weights_from_tensor`` so engine RPC call recording stays complete. - Renamed ``test_trainer_send_weights_uses_single_llm_handle_per_rank`` -> ``test_send_via_ipc_dispatches_update_weights_from_tensor_with_version``, asserts the new RPC name + kwargs (``update_info``, ``weight_version``) and that ``finish_weight_update`` is now stateless (no kwargs). - Added ``test_update_weights_from_tensor_posts_ipc_update_info_and_records_version``: asserts ipc_handles get cloudpickle'd into ipc_handles_pickled, metadata fields pass through, ``_weight_version`` advances on POST success. - Added ``test_update_weights_from_tensor_does_not_advance_version_on_failure``: asserts POST failure does not advance ``_weight_version`` (matches the same post-POST ordering review note from #45). Pre-existing test failures in tests/unit/backends/vllm_utils/test_vllm_engine.py (``_weight_transfer_http_timeout``, ``_response_json_or_fallback``, ``server_host``) are unchanged from main — main has 8 failed / 24 passed, this PR has 8 failed / 26 passed (the two added tests). Not in scope here. Signed-off-by: aoshen02 <aoshen@inferact.ai>
…version-with-data) Background ---------- After PR #22 introduced the colocated CUDA IPC path, vime ended up with three ``update_weights*`` RPC entry points whose ``_weight_version`` bookkeeping was inconsistent: - ``update_weights_from_distributed`` (NCCL path): writes ``_weight_version`` inside the RPC, version travels with data — slime-style. - ``update_weights`` (IPC path, called from ``IPCWeightTransferEngine.trainer_send_weights``): forwarded vLLM's ``IPCWeightTransferUpdateInfo`` to ``/update_weights`` over HTTP but never recorded ``_weight_version`` — vLLM's payload schema does not carry it. - ``update_weights_from_tensor`` (PR #18 legacy entry): kept a SGLang-ish ``serialized_named_tensors`` payload and wrote ``_weight_version``, but had no callers in main. The IPC gap was the root cause of #41-era's "Weight version mismatch! Engine: /root/models/<...>, Updater: N" failure on every colocated test with ``--ci-test`` (fixed in #45 by piggybacking ``weight_version`` onto ``finish_weight_update``). slime's design avoids this entirely: both IPC and distributed call ``engine.update_weights_from_tensor.remote(..., weight_version=N)`` — same RPC name across both repos, with version travelling alongside the data in the same RPC. This PR ------- Rewire vime's IPC path to match slime's interface: 1. ``vllm_engine.update_weights_from_tensor`` is now the IPC entry point. Signature ``(update_info: dict, weight_version: str | None, flush_cache)``; payload carries vLLM's ``IPCWeightTransferUpdateInfo`` (names / dtype_names / shapes / ipc_handles), the trainer constructs it with ``reduce_tensor`` from ``torch.multiprocessing.reductions``. Records ``_weight_version`` only after the POST succeeds — mirrors ``update_weights_from_distributed``'s post-POST ordering so a failed transfer never advances the engine's tracked version. 2. Delete ``vllm_engine.update_weights`` — was the vLLM ``IPCWeightTransferEngine.trainer_send_weights`` entry, no longer used after step 4 below. 3. Delete ``vllm_engine._run_vllm_weight_update`` — dead helper that only ``update_weights_from_tensor``'s old SGLang-ish path called. 4. Revert ``finish_weight_update`` to a stateless POST — ``_weight_version`` now lives in the data-carrying RPC, so the bookend no longer needs to piggyback a kwarg. (Undoes the kwarg added in #45.) 5. Replace ``IPCWeightTransferEngine.trainer_send_weights(...)`` calls in ``_send_hf_chunk_via_ipc`` with direct ``engine.update_weights_from_tensor.remote(update_info=..., weight_version=...)`` for both slot_size paths (slot_size==1 and slot_size>1). vime keeps reusing vLLM's ``reduce_tensor`` for IPC handle creation (via ``_build_ipc_update_info_from_named_tensors``) — only the dispatch is ours — so we don't fork the vLLM IPC protocol, just route through our own RPC surface. Why not just keep #45's piggyback? - #45 worked but coupled version bookkeeping to the lifecycle hook ``finish_weight_update`` instead of the data RPC. The wire shape doesn't match slime's, and a new IPC-style entry point added later would have to remember to also write ``_weight_version`` — exactly the trap PR #22 fell into. Centralising the write inside the data RPC removes the trap. Unit tests ---------- - ``RecordingVLLMEngine`` learns ``update_weights_from_tensor`` so engine RPC call recording stays complete. - Renamed ``test_trainer_send_weights_uses_single_llm_handle_per_rank`` -> ``test_send_via_ipc_dispatches_update_weights_from_tensor_with_version``, asserts the new RPC name + kwargs (``update_info``, ``weight_version``) and that ``finish_weight_update`` is now stateless (no kwargs). - Added ``test_update_weights_from_tensor_posts_ipc_update_info_and_records_version``: asserts ipc_handles get cloudpickle'd into ipc_handles_pickled, metadata fields pass through, ``_weight_version`` advances on POST success. - Added ``test_update_weights_from_tensor_does_not_advance_version_on_failure``: asserts POST failure does not advance ``_weight_version`` (matches the same post-POST ordering review note from #45). Pre-existing test failures in tests/unit/backends/vllm_utils/test_vllm_engine.py (``_weight_transfer_http_timeout``, ``_response_json_or_fallback``, ``server_host``) are unchanged from main — main has 8 failed / 24 passed, this PR has 8 failed / 26 passed (the two added tests). Not in scope here. Signed-off-by: aoshen02 <aoshen@inferact.ai>
…version-with-data) Background ---------- After PR #22 introduced the colocated CUDA IPC path, vime ended up with three ``update_weights*`` RPC entry points whose ``_weight_version`` bookkeeping was inconsistent: - ``update_weights_from_distributed`` (NCCL path): writes ``_weight_version`` inside the RPC, version travels with data — slime-style. - ``update_weights`` (IPC path, called from ``IPCWeightTransferEngine.trainer_send_weights``): forwarded vLLM's ``IPCWeightTransferUpdateInfo`` to ``/update_weights`` over HTTP but never recorded ``_weight_version`` — vLLM's payload schema does not carry it. - ``update_weights_from_tensor`` (PR #18 legacy entry): kept a SGLang-ish ``serialized_named_tensors`` payload and wrote ``_weight_version``, but had no callers in main. The IPC gap was the root cause of #41-era's "Weight version mismatch! Engine: /root/models/<...>, Updater: N" failure on every colocated test with ``--ci-test`` (fixed in #45 by piggybacking ``weight_version`` onto ``finish_weight_update``). slime's design avoids this entirely: both IPC and distributed call ``engine.update_weights_from_tensor.remote(..., weight_version=N)`` — same RPC name across both repos, with version travelling alongside the data in the same RPC. This PR ------- Rewire vime's IPC path to match slime's interface: 1. ``vllm_engine.update_weights_from_tensor`` is now the IPC entry point. Signature ``(update_info: dict, weight_version: str | None, flush_cache)``; payload carries vLLM's ``IPCWeightTransferUpdateInfo`` (names / dtype_names / shapes / ipc_handles), the trainer constructs it with ``reduce_tensor`` from ``torch.multiprocessing.reductions``. Records ``_weight_version`` only after the POST succeeds — mirrors ``update_weights_from_distributed``'s post-POST ordering so a failed transfer never advances the engine's tracked version. 2. Delete ``vllm_engine.update_weights`` — was the vLLM ``IPCWeightTransferEngine.trainer_send_weights`` entry, no longer used after step 4 below. 3. Delete ``vllm_engine._run_vllm_weight_update`` — dead helper that only ``update_weights_from_tensor``'s old SGLang-ish path called. 4. Revert ``finish_weight_update`` to a stateless POST — ``_weight_version`` now lives in the data-carrying RPC, so the bookend no longer needs to piggyback a kwarg. (Undoes the kwarg added in #45.) 5. Replace ``IPCWeightTransferEngine.trainer_send_weights(...)`` calls in ``_send_hf_chunk_via_ipc`` with direct ``engine.update_weights_from_tensor.remote(update_info=..., weight_version=...)`` for both slot_size paths (slot_size==1 and slot_size>1). vime keeps reusing vLLM's ``reduce_tensor`` for IPC handle creation (via ``_build_ipc_update_info_from_named_tensors``) — only the dispatch is ours — so we don't fork the vLLM IPC protocol, just route through our own RPC surface. Why not just keep #45's piggyback? - #45 worked but coupled version bookkeeping to the lifecycle hook ``finish_weight_update`` instead of the data RPC. The wire shape doesn't match slime's, and a new IPC-style entry point added later would have to remember to also write ``_weight_version`` — exactly the trap PR #22 fell into. Centralising the write inside the data RPC removes the trap. Unit tests ---------- - ``RecordingVLLMEngine`` learns ``update_weights_from_tensor`` so engine RPC call recording stays complete. - Renamed ``test_trainer_send_weights_uses_single_llm_handle_per_rank`` -> ``test_send_via_ipc_dispatches_update_weights_from_tensor_with_version``, asserts the new RPC name + kwargs (``update_info``, ``weight_version``) and that ``finish_weight_update`` is now stateless (no kwargs). - Added ``test_update_weights_from_tensor_posts_ipc_update_info_and_records_version``: asserts ipc_handles get cloudpickle'd into ipc_handles_pickled, metadata fields pass through, ``_weight_version`` advances on POST success. - Added ``test_update_weights_from_tensor_does_not_advance_version_on_failure``: asserts POST failure does not advance ``_weight_version`` (matches the same post-POST ordering review note from #45). Pre-existing test failures in tests/unit/backends/vllm_utils/test_vllm_engine.py (``_weight_transfer_http_timeout``, ``_response_json_or_fallback``, ``server_host``) are unchanged from main — main has 8 failed / 24 passed, this PR has 8 failed / 26 passed (the two added tests). Not in scope here. Signed-off-by: aoshen02 <aoshen@inferact.ai>
…version-with-data) (#48) * refactor(weight-sync): align IPC RPC contract with slime (single-RPC version-with-data) Background ---------- After PR #22 introduced the colocated CUDA IPC path, vime ended up with three ``update_weights*`` RPC entry points whose ``_weight_version`` bookkeeping was inconsistent: - ``update_weights_from_distributed`` (NCCL path): writes ``_weight_version`` inside the RPC, version travels with data — slime-style. - ``update_weights`` (IPC path, called from ``IPCWeightTransferEngine.trainer_send_weights``): forwarded vLLM's ``IPCWeightTransferUpdateInfo`` to ``/update_weights`` over HTTP but never recorded ``_weight_version`` — vLLM's payload schema does not carry it. - ``update_weights_from_tensor`` (PR #18 legacy entry): kept a SGLang-ish ``serialized_named_tensors`` payload and wrote ``_weight_version``, but had no callers in main. The IPC gap was the root cause of #41-era's "Weight version mismatch! Engine: /root/models/<...>, Updater: N" failure on every colocated test with ``--ci-test`` (fixed in #45 by piggybacking ``weight_version`` onto ``finish_weight_update``). slime's design avoids this entirely: both IPC and distributed call ``engine.update_weights_from_tensor.remote(..., weight_version=N)`` — same RPC name across both repos, with version travelling alongside the data in the same RPC. This PR ------- Rewire vime's IPC path to match slime's interface: 1. ``vllm_engine.update_weights_from_tensor`` is now the IPC entry point. Signature ``(update_info: dict, weight_version: str | None, flush_cache)``; payload carries vLLM's ``IPCWeightTransferUpdateInfo`` (names / dtype_names / shapes / ipc_handles), the trainer constructs it with ``reduce_tensor`` from ``torch.multiprocessing.reductions``. Records ``_weight_version`` only after the POST succeeds — mirrors ``update_weights_from_distributed``'s post-POST ordering so a failed transfer never advances the engine's tracked version. 2. Delete ``vllm_engine.update_weights`` — was the vLLM ``IPCWeightTransferEngine.trainer_send_weights`` entry, no longer used after step 4 below. 3. Delete ``vllm_engine._run_vllm_weight_update`` — dead helper that only ``update_weights_from_tensor``'s old SGLang-ish path called. 4. Revert ``finish_weight_update`` to a stateless POST — ``_weight_version`` now lives in the data-carrying RPC, so the bookend no longer needs to piggyback a kwarg. (Undoes the kwarg added in #45.) 5. Replace ``IPCWeightTransferEngine.trainer_send_weights(...)`` calls in ``_send_hf_chunk_via_ipc`` with direct ``engine.update_weights_from_tensor.remote(update_info=..., weight_version=...)`` for both slot_size paths (slot_size==1 and slot_size>1). vime keeps reusing vLLM's ``reduce_tensor`` for IPC handle creation (via ``_build_ipc_update_info_from_named_tensors``) — only the dispatch is ours — so we don't fork the vLLM IPC protocol, just route through our own RPC surface. Why not just keep #45's piggyback? - #45 worked but coupled version bookkeeping to the lifecycle hook ``finish_weight_update`` instead of the data RPC. The wire shape doesn't match slime's, and a new IPC-style entry point added later would have to remember to also write ``_weight_version`` — exactly the trap PR #22 fell into. Centralising the write inside the data RPC removes the trap. Unit tests ---------- - ``RecordingVLLMEngine`` learns ``update_weights_from_tensor`` so engine RPC call recording stays complete. - Renamed ``test_trainer_send_weights_uses_single_llm_handle_per_rank`` -> ``test_send_via_ipc_dispatches_update_weights_from_tensor_with_version``, asserts the new RPC name + kwargs (``update_info``, ``weight_version``) and that ``finish_weight_update`` is now stateless (no kwargs). - Added ``test_update_weights_from_tensor_posts_ipc_update_info_and_records_version``: asserts ipc_handles get cloudpickle'd into ipc_handles_pickled, metadata fields pass through, ``_weight_version`` advances on POST success. - Added ``test_update_weights_from_tensor_does_not_advance_version_on_failure``: asserts POST failure does not advance ``_weight_version`` (matches the same post-POST ordering review note from #45). Pre-existing test failures in tests/unit/backends/vllm_utils/test_vllm_engine.py (``_weight_transfer_http_timeout``, ``_response_json_or_fallback``, ``server_host``) are unchanged from main — main has 8 failed / 24 passed, this PR has 8 failed / 26 passed (the two added tests). Not in scope here. Signed-off-by: aoshen02 <aoshen@inferact.ai> * fix(weight-sync): correct IPC slot leader gating and gather group Two regressions in the previous commit only fire when Megatron TP != rollout-num-gpus-per-engine (e.g. parallel-check sweeps Megatron TP=1 with rollout TP=2). Both surface via ``tests/test_qwen3_0.6B_parallel_check.py``. Bug 1: leader gating wrong reference group ------------------------------------------ ``connect_rollout_engines`` used:: if mpu.get_tensor_model_parallel_rank() == 0: self._ipc_engine_coordinator = True The intent was "TP rank 0 within the engine GPU slot", but ``mpu.get_tensor_model_parallel_rank()`` is the Megatron TP rank, not the engine-slot rank. When Megatron TP=1, every trainer rank sees ``tp_rank=0`` and becomes a coordinator. For slot_size > 1, both ranks in the slot then call ``start_weight_update`` → the second call explodes:: Worker failed with error 'start_weight_update called while a weight update is already active. Call finish_weight_update first.' Fix: gate on ``rank == start`` (lowest trainer rank in the engine GPU range). Unique per slot regardless of Megatron parallelism. Bug 2: gather group wrong scope ------------------------------- ``_send_hf_chunk_via_ipc`` used ``mpu.get_tensor_model_parallel_group()`` to all_gather IPC payloads from peers in the engine slot. Again Megatron TP group ≠ engine slot when their world sizes differ. The merge then only had the coordinator's own UUID; downstream workers reading a different physical GPU got:: ValueError: IPC handle not found for GPU UUID <peer>. Available UUIDs: ['<coordinator>'] Fix: build per-slot process groups in ``connect_rollout_engines`` collectively (every trainer rank calls ``dist.new_group(slot_ranks)`` for every engine slot, keeps the one it belongs to). Use that group instead of Megatron's TP group for the gather and the trailing barrier. Validation ---------- Ran ``tests/test_qwen3_0.6B_parallel_check.py`` on 8×H200 with ``--num-rollout 2``. The test sweeps tp_size ∈ {1, 2, 4, 8} × pp_size ∈ {1, 2, 4} × cp_size ∈ {1, 2, 4, 8} for num_gpus ∈ {8, 4, 2} — every leg also uses ``--rollout-num-gpus-per-engine 2``, so the Megatron-TP=1 cases now exercise the new slot-group path. Pre-fix: fails on the very first Megatron-TP=1 config with bug 1 above; after bug 1 is patched, the next iteration fails with bug 2. Post-fix: the entire ~2-hour sweep completes with "Job succeeded" on every leg. Other tests already exercising IPC at Megatron-TP=2 == rollout-TP=2 are unaffected by this fix (``rank == start`` is equivalent to ``tp_rank == 0`` when the slot fits a single Megatron TP group). The following also pass post-fix as a sanity check: ``test_qwen3_4B_ppo``, ``test_qwen3_4B_ppo_train_critic_only``, ``test_qwen3_4B_ppo_disaggregate``, ``test_mimo_7B_mtp_only_grad``, ``test_moonlight_16B_A3B``, ``test_quick_start_glm4_9B``, ``test_qwen2.5_0.5B_{short,async_short,debug_rollout_then_train, ppo_critic_only_short}``, ``test_qwen3.5_0.8B_gsm8k_{short,async_short}``. Signed-off-by: aoshen02 <aoshen@inferact.ai> 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> * fix(weight-sync): use gloo backend for ipc payload gather, add multi-gpu test Co-authored-by: Cursor <cursoragent@cursor.com> Signed-off-by: SamitHuang <285365963@qq.com> Co-authored-by: Cursor <cursoragent@cursor.com> * refactor(weight-sync): drop dead _apply_monkey_patch_torch_reductions calls The two _apply_monkey_patch_torch_reductions() call sites in this file (trainer send + vLLM worker hijack) are no-ops on the IPC path here: 1. We route IPC handles by physical GPU UUID dict key (set on the trainer side at _build_ipc_update_info_from_named_tensors via _current_gpu_uuid() from torch.cuda.get_device_properties().uuid). The receiver looks up by its own UUID, independent of args[6]. 2. vLLM's IPCWeightTransferEngine.receive_weights unconditionally overwrites args[6] with the receiver's local device_index before calling rebuild_cuda_tensor. Whatever a torch reductions patch encodes into args[6] is therefore discarded. The patch was the historical mechanism (sglang upstream) for translating device indices across CUDA_VISIBLE_DEVICES boundaries by stuffing UUID strings into args[6]. Our UUID-keyed dict + vLLM's explicit device_index override accomplish the same thing without the global torch reductions mutation. Also expand the _build_ipc_update_info_from_named_tensors docstring to spell out the UUID-keyed routing contract so future readers don't have to chase this through git history. Side effect: hf_weight_iterator_direct.py also calls monkey_patch_torch_reductions() at module-collective time. That call site is similarly decorative (only NCCL broadcast / all_gather collectives run there, no cross-process pickling) but lives outside this file's scope and is not touched here. Tracked alongside #29. * refactor(weight-sync): finish removing monkey_patch_torch_reductions dead code Follow-up to 39bf899 (deleted _apply_monkey_patch_torch_reductions from update_weight_from_tensor.py). With that helper gone, two more references are now dead in the vime IPC weight-transfer path: 1. hf_weight_iterator_direct.py:48 called monkey_patch_torch_reductions() at the top of _get_megatron_full_params(). On vime this never has effect on the IPC handle path: _get_megatron_full_params only runs NCCL broadcast/all_gather collectives (no cross-process pickling), and the chunks it returns are subsequently sent via PR #48's UUID-keyed {gpu_uuid: reduce_tensor(weight)} dict that vLLM's receiver routes by physical UUID + explicit args[6] overwrite. The call survives in slime/ miles upstream because their downstream path pickles tensors through sglang's MultiprocessingSerializer.serialize (ForkingPickler → reduce_tensor), where the patched encoding/decoding does real work; PR #48 does not use that pipeline, so the call here was incidentally inherited rather than functionally required. 2. slime/backends/megatron_utils/sglang.py's monkey_patch_torch_reductions re-export + __all__ entry now have no remaining importers in vime. Remove them. Also (this commit, B): 3. vllm_engine.py's update_weights_from_tensor docstring referred to "closures injected by _apply_monkey_patch_torch_reductions" as the reason for cloudpickle. That helper is gone; the cloudpickle is still correct because reduce_tensor returns a (rebuild_fn, args) tuple where the rebuild_fn is a module-level callable that JSON can't serialise. Update the docstring to reflect the actual reason. Net behaviour: identical — the deletions remove dead code paths. The patch_torch shim itself is still importable for callers outside vime (none currently in this tree). Cross-references: - #29 — issue documenting the no-op stub - 39bf899 — prior commit that deleted the helper from update_weight_from_tensor.py * docs(weight-sync): drop sglang refs + add IPC call-stack notes - update_weight_from_tensor.py module docstring: rewrite from a pure vLLM perspective. Step (2) now spells out the merged {uuid_G0: handle, uuid_G1: handle, ...} dict + collective_rpc fan-out inside the vLLM server, and step (3) makes version-with-data atomicity explicit. Drop the "match slime's sglang_engine signature" framing. - vllm_engine.update_weights_from_tensor: collapse the long sglang-vs-vLLM compare block into a focused docstring describing what the POST does and why ipc_handles needs cloudpickle. Add a Chinese call-stack walkthrough (trainer → ★this method★ → server collective_rpc → per-TP worker receive_weights) and note that `node_rank != 0` is a dead branch since VLLMEngine pins node_rank=0 (see PR #48 review comment for the follow-up cleanup). - Hoist base64/cloudpickle imports to module scope so the hot path no longer pays the per-call import overhead. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> --------- Signed-off-by: aoshen02 <aoshen@inferact.ai> Signed-off-by: SamitHuang <285365963@qq.com> Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: SamitHuang <285365963@qq.com> Co-authored-by: Cursor <cursoragent@cursor.com>
The 786-line tests/test_update_weight_from_tensor.py is a stale rebase leftover from the original PR #18 branch — it predates the IPC test file PR #22 landed at the canonical unit-test path (tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py) and predates PR #48's single-RPC weight-version contract. Comparing the two: * Both stub sys.modules / torch.distributed at module import time, so having two files compounds the test-isolation issue Gemini raised (PR #40 comment #1). * Coverage overlaps materially (e.g. test_ipc_init_called_on_first_update_only ≈ test_ipc_init_runs_once — same invariant, different wording). * The nested file is up-to-date with PR #48's RPC contract (update_weights_from_tensor.remote(**fields, weight_version=...)); the top-level file still uses the pre-#48 lifecycle shape and does not exercise the coordinator slot fields. * The nested path matches repo convention: tests/unit/ for mock-only unit tests, tests/ top level for e2e scripts. Closes Gemini comment #1 on PR #40. Gemini comment #2 (the same stub pattern in the surviving nested file) is a pre-existing issue from PR #22 / #48 and out of scope for this rename PR — to be addressed in a follow-up that converts _install_stubs() to an autouse module-scoped fixture with save/restore. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* tests + CI: complete sglang→vllm rename across tests/ and .github/ Split from PR #18 (gcl/clean-sglang). One of 4 PRs splitting the original PR #18 by content area: docs (#38) / examples (#39) / **tests+CI** / core runtime. 42 files / +~750 / -~700. These are bundled in a single PR because the CI workflows reference test file names by string — splitting them would create a window where either tests are renamed but CI still points at the old names, or vice versa, breaking CI mid-roll. What this PR does: (A) tests/ (38 files): - Mechanical CLI-flag rename: --sglang-* → --vllm-* equivalents in all test scripts (matches the table now used in scripts/ and examples/). - Variable rename: SGLANG_ARGS → VLLM_ARGS where present. - 4 file renames (R086-R091, all >85% similarity): test_qwen2.5_0.5B_opd_sglang.py → test_qwen2.5_0.5B_opd_vllm.py test_qwen2.5_0.5B_sglang_config.py → test_qwen2.5_0.5B_vllm_config.py test_qwen2.5_0.5B_sglang_config_distributed.py → test_qwen2.5_0.5B_vllm_config_distributed.py test_sglang_config_mixed_offload.py → test_vllm_config_mixed_offload.py test_sglang_config_mixed_offload_ft.py → test_vllm_config_mixed_offload_ft.py tests/utils/test_sglang_config.py → tests/utils/test_vllm_config.py - 2 new tests for the IPC weight-transfer path landed in PR #18: tests/test_update_weight_from_tensor.py tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py (These are PR #22 / colocate-IPC test coverage; the production code the slim PR #18 ships will rely on the same code from PR #22.) (B) .github/ (4 files): - workflows/conda-ci.yml: container image lmsysorg/sglang → vime (inferactinc/public:vime-vllm-cu129-latest). - workflows/pr-test.yml + pr-test.yml.j2 (template): * Container images (slimerl/slime[-test]:latest → vime image) on every job that ran on the sglang-era base. * e2e-test-sglang-config job → e2e-test-vllm-config job (renamed label `run-ci-sglang-config` → `run-ci-vllm-config`; matrix `test_file` entries updated to point at the renamed test files in (A)). * e2e-test-megatron + e2e-test-image matrices: `_opd_sglang.py` entries → `_opd_vllm.py`. - ISSUE_TEMPLATE/bug_report.yml: drop the "SGLang version (if relevant):" environment field, add "vLLM version:" and "vllm-router version:" lines. (PR #36 already changed "CUDA/ROCm version" → "CUDA version" earlier; that change is preserved.) Sgl residue intentionally kept (4 hits — all anti-regression assertions that prove sglang code paths are gone, not residual references to bring back): - tests/test_update_weight_from_tensor.py:753 — comment "The vLLM IPC implementation must NOT contain sglang-style Gloo gather code". - tests/unit/backends/vllm_utils/test_arguments.py:233-237 — three assertions that --sglang-router-ip, --sglang-router-port, and sglang_router_ip are NOT present in the argument parser. Tests + CI must land together; splitting them risks a window where the CI matrix references test files by names that don't exist yet (or no longer exist). After this lands, the test_file string in CI matches the test files on disk. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com> * on_policy_distillation: port from SGLang to vLLM /v1/completions Follow-up on the test rename in this PR: test_qwen2.5_0.5B_opd_sglang.py → test_qwen2.5_0.5B_opd_vllm.py. The test only spawns a vLLM teacher and exercises the OPD pipeline; the real broken piece was slime/rollout/on_policy_distillation.py, which PR #18 left in SGLang request/response shape: request fields: "max_new_tokens": 0 (vLLM: "max_tokens") "return_logprob": True (sglang-only) "logprob_start_len": 0 (sglang-only) response parsing: reward["meta_info"]["input_token_logprobs"] (sglang shape) vLLM 0.21 supports the same workflow natively via `prompt_logprobs`: request to POST /v1/completions: { "model": <teacher>, "prompt_token_ids": sample.tokens, "max_tokens": 1, "temperature": 0, "prompt_logprobs": 1, "logprobs": 0, "skip_special_tokens": False, } response: response["choices"][0]["prompt_logprobs"] # list[dict[int, Logprob] | None] where Logprob is {"logprob": float, "rank": int, "decoded_token": str} References checked against vllm source: - reference/vllm/vllm/entrypoints/openai/completion/protocol.py:91 (request: prompt_logprobs: int | None) - reference/vllm/vllm/entrypoints/openai/completion/protocol.py:487 (response: prompt_logprobs: list[dict[int, Logprob] | None] | None) - reference/vllm/vllm/logprobs.py:13 (Logprob dataclass: logprob/rank/decoded_token) Implementation notes: 1. JSON serializes int dict keys as strings, so `_logprob_for_token` tries both `pos_entry.get(token_id)` and `pos_entry.get(str(token_id))`. 2. `pos_entry` is `None` at position 0 (no prior context) — handled explicitly. We also gracefully degrade if a token at position `i` is not in the top-1 logprob dict (falls back to 0.0, same as the prior sglang code would do). 3. The Logprob dataclass `decoded_token` field is unused; we only read `.logprob`. Both dict and `Logprob` shapes are accepted in case the server uses a flatter serialization toggle. 4. `args.opd_teacher_model` is the new model-name arg; falls back to `args.hf_checkpoint` if not set, mirroring how vime's other rollout paths derive the model name. Smoke-tested `_logprob_for_token` locally: - None entry → 0.0 - int key + dict value → logprob - str key (JSON shape) → logprob - missing token → 0.0 - flattened float value → float Also drops 3 lines from tests/unit/backends/vllm_utils/test_arguments.py: the `--sglang-router-ip`/`--sglang-router-port`/`sglang_router_ip` anti- regression assertions. Once the slim PR #18 lands and sglang is gone from the runtime, those assertions are vacuous; treating sglang as non-existent per the project policy. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com> * tests: drop duplicate smoke test updates from PR40 * test(update_weight_from_tensor): drop stale _apply_monkey_patch_torch_reductions patch The inner ``with patch(f"{MODULE_PATH}._apply_monkey_patch_torch_reductions"):`` context in _run_update suppressed a helper call that PR #48 has since deleted from update_weight_from_tensor.py (commit 39bf899 on aoshen/align-ipc-rpc-with-slime). After that PR lands the patched attribute won't exist and this line raises AttributeError. Remove it now so the test survives PR #48 merge. The ``sglang_mod.monkey_patch_torch_reductions = MagicMock()`` stub on the fake sglang module is intentionally kept: on this branch the production code still imports it via ``from ..sglang import monkey_patch_torch_reductions`` (both update_weight_from_tensor._apply_monkey_patch_torch_reductions on PR #40's view of main, and hf_weight_iterator_direct.py at module level). Removing the stub here would break the test on PR #40 alone; it can be dropped in a follow-up once PR #48 finishes removing every import site. Tests: ``tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py`` all 6 pass with this change applied to gcl/pr18-tests-ci HEAD. * tests: drop duplicate top-level test_update_weight_from_tensor.py The 786-line tests/test_update_weight_from_tensor.py is a stale rebase leftover from the original PR #18 branch — it predates the IPC test file PR #22 landed at the canonical unit-test path (tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py) and predates PR #48's single-RPC weight-version contract. Comparing the two: * Both stub sys.modules / torch.distributed at module import time, so having two files compounds the test-isolation issue Gemini raised (PR #40 comment #1). * Coverage overlaps materially (e.g. test_ipc_init_called_on_first_update_only ≈ test_ipc_init_runs_once — same invariant, different wording). * The nested file is up-to-date with PR #48's RPC contract (update_weights_from_tensor.remote(**fields, weight_version=...)); the top-level file still uses the pre-#48 lifecycle shape and does not exercise the coordinator slot fields. * The nested path matches repo convention: tests/unit/ for mock-only unit tests, tests/ top level for e2e scripts. Closes Gemini comment #1 on PR #40. Gemini comment #2 (the same stub pattern in the surviving nested file) is a pre-existing issue from PR #22 / #48 and out of scope for this rename PR — to be addressed in a follow-up that converts _install_stubs() to an autouse module-scoped fixture with save/restore. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> * test(vllm_config): use real get_model_url default endpoint /inference/v1/generate get_model_url defaults to /inference/v1/generate (PR #18), not /v1/completions. Aligns this test with PR #18's test_vllm_config.py so the two PRs no longer conflict on this file and the assertion matches the actual runtime default. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * Drop on_policy_distillation.py from tests+CI PR (now owned by runtime PR #18) The OPD vLLM /v1/completions migration is a runtime change; it was folded into the core-runtime PR (#18). Restore this file to main here so the two PRs no longer overlap on it. #18 merges first, so this lands via #18. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * Drop unit-test files now owned by runtime PR #18 test_vllm_config.py + the plugin_contracts tests are coupled to #18's runtime rename (they import vllm_config / vllm_rollout, which #18 creates). They live in #18; remove them here so the two PRs don't overlap. #18 merges first. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test: restore vLLM rollout args dropped during sglang→vllm rename The mechanical sglang→vllm rename dropped several rollout knobs instead of mapping them to their vLLM equivalents, weakening CI coverage (cuda-graph capture caps, speculative decoding, expert parallel). Restore them using the mapping established by the converted production scripts on main (run-glm4.7-30B-A3B.sh / run-glm5-744B-A40B.sh), verified against vLLM AsyncEngineArgs: --sglang-cuda-graph-max-bs N -> --vllm-max-cudagraph-capture-size N --sglang-cuda-graph-bs a b c -> --vllm-cudagraph-capture-sizes a b c --sglang-ep-size N -> --vllm-enable-expert-parallel --sglang-speculative-* (eagle) -> --vllm-speculative-config '{"method":"eagle","num_speculative_tokens":K}' Also: - glm4.7 pd: fix --vllm-max-num-seqs (was 8, taken from cuda-graph-max-bs; --sglang-max-running-requests was 16) and split out cuda-graph capture. - fix sglang→rollout mis-renames in temp-file prefixes (→ vllm_*). - test_vllm_config: rename test_update_weights_default_true → test_update_weights_defaults_to_none (it asserts `is None`). Dropped sglang flags with no vLLM equivalent (enable-dp-lm-head, moe-dense-tp-size, watchdog-timeout, mamba-scheduler-strategy, disaggregation-transfer-backend, enable-metrics) stay dropped; PD KV-transfer is driven by --prefill-num-servers + the --vllm-config prefill/decode topology. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(plugin_contracts): migrate from sglang_rollout to vllm_rollout The three plugin-contract tests still imported slime.rollout.sglang_rollout and called install_stubs(with_sglang_router=True), but _shared.install_stubs already dropped that parameter — so all three failed at collection (TypeError: unexpected keyword 'with_sglang_router'). Complete the migration: - install_stubs(with_sglang_router=True, ...) -> install_stubs(...) - import generate_and_rm / generate_rollout from slime.rollout.vllm_rollout - default rollout/eval path string -> slime.rollout.vllm_rollout.generate_rollout (matches runtime default at slime/utils/arguments.py:233) - FakeGenerateState: sglang_enable_deterministic_inference -> vllm_enable_deterministic_inference, with group_sampling_seeds defaulting to None and gated on the flag (mirrors the already-migrated tests/unit/rollout/test_vllm_rollout.py). All 34 plugin-contract cases pass (were 3 collection errors before). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(update_weight_from_tensor): drop stale slime…megatron_utils.sglang mock The test pre-registered a sys.modules mock for slime.backends.megatron_utils.sglang (monkey_patch_torch_reductions), left over from when update_weight_from_tensor imported it. The module under test no longer imports that module (its real deps are get_gloo_group / HfWeightIteratorBase / update_weight_from_distributed), so the mock is dead. Removing it makes tests/ and .github/ fully sglang-free. Test still passes (7/7). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * [Clean] Remove SGLang runtime code Rebuilt against current main so the PR contains only the SGLang runtime removal -- the docs / tests-ci / examples / scripts / docker portions were split into separate PRs that have since merged. - Delete dead SGLang server/runtime code: sglang_utils/{arguments,sglang_engine}.py, rollout/sglang_rollout.py, the megatron_utils/sglang.py re-export shim, and all docker/**/sglang.patch files. - Rename the rollout config module sglang_utils/sglang_config.py -> vllm_utils/vllm_config.py (SglangConfig -> VllmConfig, _resolve_sglang_config -> _resolve_vllm_config, --sglang-config -> --vllm-config); inline the GPU_MEMORY_TYPE_* constants in rollout.py. - Add megatron_utils/fp8_helpers.py for the UE8M0 fp8 helpers formerly re-exported through the sglang shim; repoint quantizer_fp8 to it. - Swap sglang_router -> vllm_router in http_utils/wandb_utils; drop the dead sglang-router dependency from requirements.txt. - Finish the SGLang->vLLM rename in the runtime so it is internally consistent and matches the tests landing in the tests/CI PR: * router args --router-* -> --vllm-router-* (vllm_router_ip/port/timeout); * get_model_url reads vllm_model_routers (aligning with rollout.py); * --opd-type sglang -> vllm; engine_overrides rename; * sglang_enable_deterministic_inference -> vllm_enable_deterministic_inference, wired to a real --vllm-enable-deterministic-inference flag (exports VLLM_BATCH_INVARIANT=1); * consistent_hash session-id routing uses vllm-router's x-session-id header; * drop dead trace helper build_sglang_meta_trace_attrs; de-SGLang comments/docstrings. - Rename test_sglang_config.py -> test_vllm_config.py and de-SGLang the plugin-contract tests. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * Address review: finish de-SGLang + fold OPD/router-policy into runtime - naming: replace residual generic "rollout engine"/"engine"/"comm" wording with concrete vLLM (engine_overrides -> vllm_overrides; arguments help text; http_utils comments; rollout.py "inference workers"). sglang->vllm is correct, sglang->generic is not. - megatron_to_hf: drop the q_a_proj/kv_a_proj_with_mqa pairing + _cached_tensors global. That was sglang-only: sglang's loader torch.cat's both shards within a single load_weights call (needs them co-bucketed), whereas vLLM loads each shard independently via stacked_params_mapping into fused_qkv_a_proj. Also fix the misleading "merge into single fused name" comment. - docker/Dockerfile: remove now-dead sglang/sglang-router --no-deps stubs + the build-time `import sglang` smoke check (slime no longer imports sglang_router). - OPD: migrate on_policy_distillation.py teacher logprobs to vLLM /v1/completions (prompt_logprobs) instead of sglang return_logprob / meta_info.input_token_logprobs. - routing replay: register --vllm-router-policy (dest=router_policy) so the consistent_hash x-session-id session-affinity path is actually wired (was dead). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * Review follow-ups: mirror slime vllm_config parsing + restore vLLM process cleanup - vllm_config.from_yaml: drop the needless `models_raw` intermediate and iterate `data["vllm"]` directly, restoring the "Accept both server_groups / legacy engine_groups" comment -- mirrors slime's sglang_config.from_yaml line-for-line. - command_utils.execute_train: re-add a process kill for leftover rollout engines as `pkill -9 -f "vllm serve"` (the old `pkill -9 sglang` was dropped with no vLLM equivalent), so stale engines don't hold GPUs/ports across runs. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * Drop test changes from runtime PR; tests live in the tests+CI PR (#40) The plugin_contracts tests and the test_sglang_config -> test_vllm_config rename are coupled to the test/CI rename effort and are owned by #40. Restore them to main here so #18 is purely the SGLang runtime removal. #18 merges first; #40 rebases and re-lands the vLLM test versions. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fp8_helpers: copy SGLang verbatim (fix import crash); pin vLLM deep_gemm env - fp8_helpers.py: replace the bespoke rewrite with SGLang's exact implementations of quant_weight_ue8m0 / transform_scale_ue8m0 and their DeepGEMM helpers (per_block_cast_to_fp8, ceil_to_ue8m0, ceil_div, ceil_align, the torch-impl packer). deep_gemm is imported lazily inside the functions (as SGLang does), so module import no longer requires deep_gemm. This fixes the module-level `NameError: _get_tma_aligned_size` that crashed `import megatron_to_hf` on any deep_gemm image, and drops the invented sf-stride fixup block that was not in upstream. Only should_deepgemm_weight_requant_ue8m0 stays vLLM-adapted (is_deep_gemm_e8m0_used) since SGLang's reads SGLang-internal deep_gemm_wrapper. - vllm_engine.launch_server_process: set VLLM_USE_DEEP_GEMM=1 + VLLM_DEEP_GEMM_WARMUP=relax explicitly (setdefault) alongside VLLM_BATCH_INVARIANT, replacing SGLang's removed deep_gemm precompile/warmup envs. All vLLM engine env now lives in the subprocess env builder (single source of truth). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fp8_helpers: revert to vLLM impl + fix the import NameError; add vLLM trace attrs - fp8_helpers.py: keep the vLLM-based implementation (uses vllm.utils.deep_gemm, consistent with the vLLM runtime) rather than the SGLang verbatim copy. Fix the module-level crash: the `try` block referenced `_get_tma_aligned_size` before it was bound (the "pre-imported with fallback" import was never written), which raised NameError whenever deep_gemm imported successfully -- and NameError is not caught by `except ImportError`, so `import megatron_to_hf` crashed on any deep_gemm image. Replace the bogus self-assignment with the real import: `from vllm.utils.deep_gemm import get_tma_aligned_size as _get_tma_aligned_size`. - trace_utils/vllm_rollout: add build_vllm_meta_trace_attrs and attach finish_reason + token usage to the vllm_inference_generate span (mirrors SGLang's build_sglang_meta_trace_attrs; vLLM responses lack the pd_* timing, which lives in vLLM's own OTLP traces). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(opd): score teacher via /inference/v1/generate with prompt_logprobs Move the vllm OPD teacher path off the OpenAI /v1/completions endpoint onto vime's native /inference/v1/generate (the same endpoint the rollout engines use), and fix three latent issues: 1. model field: /inference/v1/generate takes `model` as OPTIONAL. Stop defaulting to args.hf_checkpoint (the *student* name, which mis-names a teacher!=student server). Add --opd-teacher-model; send `model` only when set, otherwise omit it (single-model teacher servers use their loaded model). 2. multimodal: the old code sent image_data to a token-only endpoint, which is invalid. Raise NotImplementedError until the /v1/chat/completions/render -> /inference/v1/generate flow is wired (mirrors slime.rollout.vllm_rollout.generate). 3. logprob robustness: read top-level GenerateResponse.prompt_logprobs, assert it is present and length-aligned with token_ids, assert the per-sample tensor covers response_length, and raise (not silently return 0.0) on a missing token logprob. vLLM always includes the actual prompt token in prompt_logprobs, so a miss is a real error. Alignment is unchanged (plp[i] <-> tokens[i], skip pos 0, take [-response_length:]). Follow-up (separate, in the tests PR): the OPD e2e test must launch a teacher that exposes /inference/v1/generate and point --rm-url at it. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * chore(clean-sglang): purge SGLang from tools, train scripts, and build infra tools/: drop dead `args.sglang_enable_ep_moe` shim (read nowhere); reword profile/replay helpers to vLLM and map analyzer hints to vLLM flags (--enforce-eager, --gpu-memory-utilization). train{,_async}.py: comments SGLang -> vLLM. build infra: remove build_conda.sh (SGLang-only conda path); drop the GB300 sgl-kernel install from the Dockerfile; delete docker/npu_patch/ wholesale. docker base image: bump to vLLM v0.22.0. justfile ARM recipes now pin the real multi-arch vLLM base images instead of the dead SGLANG_IMAGE_TAG/ ENABLE_SGLANG_PATCH build-args -- cu129-arm64 -> v0.22.0-cu129-ubuntu2404 (CUDA 12.9), cu13-arm64 -> v0.22.0-ubuntu2404 (the default-CUDA tag is already CUDA 13.0) + ENABLE_CUDA_13=1. vLLM tags are multi-arch manifests, so docker selects the arm64 image automatically on an ARM host. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * ci(clean-sglang): drop conda-build workflow (ran deleted build_conda.sh on SGLang image) The single build-conda job ran `bash build_conda.sh` (removed in the previous commit) inside an lmsysorg/sglang container. With the SGLang-only conda path gone, the whole workflow is dead. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * chore(clean-sglang): fix stale SGLang refs in docs/skills; tidy comments docs/conf.py: point the "edit on GitHub" links at vllm-project/vime instead of the inherited sgl-project.github.io repo. .claude/skills/*: update the dead `slime/rollout/sglang_rollout.py` references to `vllm_rollout.py` (the real default is slime.rollout.vllm_rollout.generate_rollout). justfile: drop the redundant BASE_IMAGE override on release-cu129-arm64 (it equalled the Dockerfile default; the multi-arch manifest already resolves arm64). train{,_async}.py: drop stray "the" in the W&B comment. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(tests): use method=mtp (not eagle) in vllm speculative config The migrated speculative configs pass no draft `model`, so method=eagle raises "num_speculative_tokens was provided but without speculative model" in vLLM's SpeculativeConfig. These models carry embedded MTP layers, so method=mtp is correct and unblocks the mimo MTP-only-grad test (#19). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * fix(cleanup): target renamed vLLM subprocesses in pkill so VRAM is freed vLLM's set_process_title() renames the VRAM-holding subprocesses (VLLM::EngineCore, VLLM::Worker_TP*, vllm::router), so their cmdline no longer contains "vllm serve". The previous `pkill -9 -f "vllm serve"` matched only the launcher and left engine/worker children holding GPU memory, leaking it into the next run — masked only by the indiscriminate `pkill -9 python`, which is unsafe on colocate/shared nodes. Match both the launcher and the renamed children with `pkill -9 -f '[v]llm serve|VLL[M]::'`; the [v]/[M] bracket trick keeps the pattern from matching pkill's own cmdline. This makes the broad python kill unnecessary, so its already-commented-out lines are removed. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * fix(speculative): use method=mtp (not eagle) for embedded-MTP models vLLM's SpeculativeConfig requires an explicit draft `model` for method=eagle; with only num_speculative_tokens set it raises "num_speculative_tokens was provided but without speculative model". The migrated configs in scripts/examples/docs pass no model, so they must use method=mtp, which reuses the target checkpoint's embedded MTP layer (DeepSeek-R1, GLM-4.x-MoE, MiMo, Qwen3-Next/3.5). The two docs examples that pass an explicit "model" are genuine eagle usage and are left unchanged. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * fix(vllm): launch each rollout engine with its ServerGroup's per-group TP launch_server_process / _init_normal derived tensor-parallel size and CUDA_VISIBLE_DEVICES from the global --rollout-num-gpus-per-engine, ignoring the per-engine num_gpus_per_engine already carried on the VLLMEngine actor. A ServerGroup configured with num_gpus_per_engine greater than the global flag (e.g. tp=2) therefore launched as tp=1, while the NCCL weight-sync rendezvous sized world_size from engine_gpu_counts (the per-group value). The two disagreed: the trainer waited for a rank the under-sized engine never started, so init_weight_transfer_engine hung for 300s ("3/4 clients joined") and the job failed. Honor the per-engine num_gpus_per_engine at launch, falling back to the global flag when unset (matches the SGLang path and PR #66's _compute_server_args). Verified on H200: tests/test_qwen2.5_0.5B_vllm_config_distributed now launches engine0 tp=2 / engine1 tp=1, update_weights completes in 1.1s (was a 301s timeout), and rollout+eval proceed. AI assistance (Claude Code) was used for this change. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(ckpt): add --dist-ckpt-optim-fully-reshardable for PAO+offload save/load test_qwen3_4B_ckpt.py uses precision-aware optimizer + cpu-offload (HybridDeviceOptimizer). Under the default dp_reshardable (bucket-centric) optimizer sharding, save/load produce unequal-length param_state lists, so dist-ckpt load fails with "Cannot merge two lists with different lengths (81 and 79)". fully_reshardable is model-centric and immune to bucket-layout changes. Verified on the r3 image (Megatron-LM 0.16.0rc0 @ 1dcf0da): save+load both succeed, and source review confirms master_param / step / HybridDeviceOptimizer sync are handled on this path. This is the flag described in PR #50 that was never actually merged. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * refactor(router-args): hybrid naming — vllm_ for ip/port, bare router_ for timeout vllm-router's RouterArgs.from_cli_args only supports prefix "" or "router_" (never "vllm_router_"), and excludes host/port from its CLI via exclude_host_port=True. So: - --vllm-router-ip / --vllm-router-port keep the vllm_ prefix: RouterArgs does not own these CLI flags, vime does (populated via _start_router's manual router_args.host/port assignment), so the vllm_ prefix is free and marks them as vime-owned endpoint config. - --router-request-timeout-secs goes bare (dest router_request_timeout_secs): it is a genuine RouterArgs field, so it shares the --router-* namespace with policy / cache_threshold / retries / … and flows through from_cli_args like the other knobs. - --vllm-router-policy keeps dest=router_policy (unchanged). Also fixes conftest fixture to seed vllm_router_ip/port (was bare router_ip/port, which never matched the vllm_engine reader) and updates README/README_zh prose. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com>
* Fix colocated mode weight sync Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com> * Fix pre-commit Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com> * Fix pre-commit Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com> * Fix test Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com> --------- Signed-off-by: knlnguyen1802 <knlnguyen1802@gmail.com>
…ses (#45) After PR #22 added the colocated CUDA IPC weight sync path, the IPC branch bypasses ``VLLMEngine.update_weights_from_tensor`` entirely (data moves through ``IPCWeightTransferEngine.trainer_send_weights`` directly, not the ``/update_weights`` RPC). That RPC is the normal place where the engine's ``self._weight_version`` gets recorded; the IPC path leaves it at the initial ``None``. The fail mode shows up the first time IPC weight sync runs with ``--ci-test``: ``actor.update_weights`` at slime/backends/megatron_utils/actor.py picks a random rollout engine, calls ``get_weight_version()``, and compares against the trainer-side ``weight_updater.weight_version``. Because the engine's ``_weight_version`` is still ``None``, ``get_weight_version`` falls back to ``GET /v1/models`` and returns the model path string (e.g. ``/root/models/Qwen2.5-0.5B-Instruct``); the updater returns the integer version string (``"1"``, ``"2"``, ...). They never match: RuntimeError: Weight version mismatch! Engine: /root/models/Qwen2.5-0.5B-Instruct, Updater: 1 Reproducer: ``tests/test_qwen2.5_0.5B_short.py`` and ``tests/test_qwen2.5_0.5B_ppo_critic_only_short.py`` once they reach ``update_weights`` — both colocate + IPC, both have ``--ci-test`` set. Thread the version through: - ``VLLMEngine.finish_weight_update(weight_version: str | None = None)`` now sets ``self._weight_version = str(weight_version)`` before issuing the ``POST /finish_weight_update``. - ``UpdateWeightFromTensor.update_weights`` (step 5) passes ``str(self.weight_version)`` when the coordinator rank fires the per-engine ``finish_weight_update`` RPC. Each colocated engine's coordinator rank fires its own ``finish_weight_update``, so every engine ends up with the new version recorded; the distributed path is unchanged. Signed-off-by: aoshen02 <aoshen@inferact.ai>
…version-with-data) (#48) * refactor(weight-sync): align IPC RPC contract with slime (single-RPC version-with-data) Background ---------- After PR #22 introduced the colocated CUDA IPC path, vime ended up with three ``update_weights*`` RPC entry points whose ``_weight_version`` bookkeeping was inconsistent: - ``update_weights_from_distributed`` (NCCL path): writes ``_weight_version`` inside the RPC, version travels with data — slime-style. - ``update_weights`` (IPC path, called from ``IPCWeightTransferEngine.trainer_send_weights``): forwarded vLLM's ``IPCWeightTransferUpdateInfo`` to ``/update_weights`` over HTTP but never recorded ``_weight_version`` — vLLM's payload schema does not carry it. - ``update_weights_from_tensor`` (PR #18 legacy entry): kept a SGLang-ish ``serialized_named_tensors`` payload and wrote ``_weight_version``, but had no callers in main. The IPC gap was the root cause of #41-era's "Weight version mismatch! Engine: /root/models/<...>, Updater: N" failure on every colocated test with ``--ci-test`` (fixed in #45 by piggybacking ``weight_version`` onto ``finish_weight_update``). slime's design avoids this entirely: both IPC and distributed call ``engine.update_weights_from_tensor.remote(..., weight_version=N)`` — same RPC name across both repos, with version travelling alongside the data in the same RPC. This PR ------- Rewire vime's IPC path to match slime's interface: 1. ``vllm_engine.update_weights_from_tensor`` is now the IPC entry point. Signature ``(update_info: dict, weight_version: str | None, flush_cache)``; payload carries vLLM's ``IPCWeightTransferUpdateInfo`` (names / dtype_names / shapes / ipc_handles), the trainer constructs it with ``reduce_tensor`` from ``torch.multiprocessing.reductions``. Records ``_weight_version`` only after the POST succeeds — mirrors ``update_weights_from_distributed``'s post-POST ordering so a failed transfer never advances the engine's tracked version. 2. Delete ``vllm_engine.update_weights`` — was the vLLM ``IPCWeightTransferEngine.trainer_send_weights`` entry, no longer used after step 4 below. 3. Delete ``vllm_engine._run_vllm_weight_update`` — dead helper that only ``update_weights_from_tensor``'s old SGLang-ish path called. 4. Revert ``finish_weight_update`` to a stateless POST — ``_weight_version`` now lives in the data-carrying RPC, so the bookend no longer needs to piggyback a kwarg. (Undoes the kwarg added in #45.) 5. Replace ``IPCWeightTransferEngine.trainer_send_weights(...)`` calls in ``_send_hf_chunk_via_ipc`` with direct ``engine.update_weights_from_tensor.remote(update_info=..., weight_version=...)`` for both slot_size paths (slot_size==1 and slot_size>1). vime keeps reusing vLLM's ``reduce_tensor`` for IPC handle creation (via ``_build_ipc_update_info_from_named_tensors``) — only the dispatch is ours — so we don't fork the vLLM IPC protocol, just route through our own RPC surface. Why not just keep #45's piggyback? - #45 worked but coupled version bookkeeping to the lifecycle hook ``finish_weight_update`` instead of the data RPC. The wire shape doesn't match slime's, and a new IPC-style entry point added later would have to remember to also write ``_weight_version`` — exactly the trap PR #22 fell into. Centralising the write inside the data RPC removes the trap. Unit tests ---------- - ``RecordingVLLMEngine`` learns ``update_weights_from_tensor`` so engine RPC call recording stays complete. - Renamed ``test_trainer_send_weights_uses_single_llm_handle_per_rank`` -> ``test_send_via_ipc_dispatches_update_weights_from_tensor_with_version``, asserts the new RPC name + kwargs (``update_info``, ``weight_version``) and that ``finish_weight_update`` is now stateless (no kwargs). - Added ``test_update_weights_from_tensor_posts_ipc_update_info_and_records_version``: asserts ipc_handles get cloudpickle'd into ipc_handles_pickled, metadata fields pass through, ``_weight_version`` advances on POST success. - Added ``test_update_weights_from_tensor_does_not_advance_version_on_failure``: asserts POST failure does not advance ``_weight_version`` (matches the same post-POST ordering review note from #45). Pre-existing test failures in tests/unit/backends/vllm_utils/test_vllm_engine.py (``_weight_transfer_http_timeout``, ``_response_json_or_fallback``, ``server_host``) are unchanged from main — main has 8 failed / 24 passed, this PR has 8 failed / 26 passed (the two added tests). Not in scope here. Signed-off-by: aoshen02 <aoshen@inferact.ai> * fix(weight-sync): correct IPC slot leader gating and gather group Two regressions in the previous commit only fire when Megatron TP != rollout-num-gpus-per-engine (e.g. parallel-check sweeps Megatron TP=1 with rollout TP=2). Both surface via ``tests/test_qwen3_0.6B_parallel_check.py``. Bug 1: leader gating wrong reference group ------------------------------------------ ``connect_rollout_engines`` used:: if mpu.get_tensor_model_parallel_rank() == 0: self._ipc_engine_coordinator = True The intent was "TP rank 0 within the engine GPU slot", but ``mpu.get_tensor_model_parallel_rank()`` is the Megatron TP rank, not the engine-slot rank. When Megatron TP=1, every trainer rank sees ``tp_rank=0`` and becomes a coordinator. For slot_size > 1, both ranks in the slot then call ``start_weight_update`` → the second call explodes:: Worker failed with error 'start_weight_update called while a weight update is already active. Call finish_weight_update first.' Fix: gate on ``rank == start`` (lowest trainer rank in the engine GPU range). Unique per slot regardless of Megatron parallelism. Bug 2: gather group wrong scope ------------------------------- ``_send_hf_chunk_via_ipc`` used ``mpu.get_tensor_model_parallel_group()`` to all_gather IPC payloads from peers in the engine slot. Again Megatron TP group ≠ engine slot when their world sizes differ. The merge then only had the coordinator's own UUID; downstream workers reading a different physical GPU got:: ValueError: IPC handle not found for GPU UUID <peer>. Available UUIDs: ['<coordinator>'] Fix: build per-slot process groups in ``connect_rollout_engines`` collectively (every trainer rank calls ``dist.new_group(slot_ranks)`` for every engine slot, keeps the one it belongs to). Use that group instead of Megatron's TP group for the gather and the trailing barrier. Validation ---------- Ran ``tests/test_qwen3_0.6B_parallel_check.py`` on 8×H200 with ``--num-rollout 2``. The test sweeps tp_size ∈ {1, 2, 4, 8} × pp_size ∈ {1, 2, 4} × cp_size ∈ {1, 2, 4, 8} for num_gpus ∈ {8, 4, 2} — every leg also uses ``--rollout-num-gpus-per-engine 2``, so the Megatron-TP=1 cases now exercise the new slot-group path. Pre-fix: fails on the very first Megatron-TP=1 config with bug 1 above; after bug 1 is patched, the next iteration fails with bug 2. Post-fix: the entire ~2-hour sweep completes with "Job succeeded" on every leg. Other tests already exercising IPC at Megatron-TP=2 == rollout-TP=2 are unaffected by this fix (``rank == start`` is equivalent to ``tp_rank == 0`` when the slot fits a single Megatron TP group). The following also pass post-fix as a sanity check: ``test_qwen3_4B_ppo``, ``test_qwen3_4B_ppo_train_critic_only``, ``test_qwen3_4B_ppo_disaggregate``, ``test_mimo_7B_mtp_only_grad``, ``test_moonlight_16B_A3B``, ``test_quick_start_glm4_9B``, ``test_qwen2.5_0.5B_{short,async_short,debug_rollout_then_train, ppo_critic_only_short}``, ``test_qwen3.5_0.8B_gsm8k_{short,async_short}``. Signed-off-by: aoshen02 <aoshen@inferact.ai> 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> * fix(weight-sync): use gloo backend for ipc payload gather, add multi-gpu test Co-authored-by: Cursor <cursoragent@cursor.com> Signed-off-by: SamitHuang <285365963@qq.com> Co-authored-by: Cursor <cursoragent@cursor.com> * refactor(weight-sync): drop dead _apply_monkey_patch_torch_reductions calls The two _apply_monkey_patch_torch_reductions() call sites in this file (trainer send + vLLM worker hijack) are no-ops on the IPC path here: 1. We route IPC handles by physical GPU UUID dict key (set on the trainer side at _build_ipc_update_info_from_named_tensors via _current_gpu_uuid() from torch.cuda.get_device_properties().uuid). The receiver looks up by its own UUID, independent of args[6]. 2. vLLM's IPCWeightTransferEngine.receive_weights unconditionally overwrites args[6] with the receiver's local device_index before calling rebuild_cuda_tensor. Whatever a torch reductions patch encodes into args[6] is therefore discarded. The patch was the historical mechanism (sglang upstream) for translating device indices across CUDA_VISIBLE_DEVICES boundaries by stuffing UUID strings into args[6]. Our UUID-keyed dict + vLLM's explicit device_index override accomplish the same thing without the global torch reductions mutation. Also expand the _build_ipc_update_info_from_named_tensors docstring to spell out the UUID-keyed routing contract so future readers don't have to chase this through git history. Side effect: hf_weight_iterator_direct.py also calls monkey_patch_torch_reductions() at module-collective time. That call site is similarly decorative (only NCCL broadcast / all_gather collectives run there, no cross-process pickling) but lives outside this file's scope and is not touched here. Tracked alongside #29. * refactor(weight-sync): finish removing monkey_patch_torch_reductions dead code Follow-up to 39bf899 (deleted _apply_monkey_patch_torch_reductions from update_weight_from_tensor.py). With that helper gone, two more references are now dead in the vime IPC weight-transfer path: 1. hf_weight_iterator_direct.py:48 called monkey_patch_torch_reductions() at the top of _get_megatron_full_params(). On vime this never has effect on the IPC handle path: _get_megatron_full_params only runs NCCL broadcast/all_gather collectives (no cross-process pickling), and the chunks it returns are subsequently sent via PR #48's UUID-keyed {gpu_uuid: reduce_tensor(weight)} dict that vLLM's receiver routes by physical UUID + explicit args[6] overwrite. The call survives in slime/ miles upstream because their downstream path pickles tensors through sglang's MultiprocessingSerializer.serialize (ForkingPickler → reduce_tensor), where the patched encoding/decoding does real work; PR #48 does not use that pipeline, so the call here was incidentally inherited rather than functionally required. 2. slime/backends/megatron_utils/sglang.py's monkey_patch_torch_reductions re-export + __all__ entry now have no remaining importers in vime. Remove them. Also (this commit, B): 3. vllm_engine.py's update_weights_from_tensor docstring referred to "closures injected by _apply_monkey_patch_torch_reductions" as the reason for cloudpickle. That helper is gone; the cloudpickle is still correct because reduce_tensor returns a (rebuild_fn, args) tuple where the rebuild_fn is a module-level callable that JSON can't serialise. Update the docstring to reflect the actual reason. Net behaviour: identical — the deletions remove dead code paths. The patch_torch shim itself is still importable for callers outside vime (none currently in this tree). Cross-references: - #29 — issue documenting the no-op stub - 39bf899 — prior commit that deleted the helper from update_weight_from_tensor.py * docs(weight-sync): drop sglang refs + add IPC call-stack notes - update_weight_from_tensor.py module docstring: rewrite from a pure vLLM perspective. Step (2) now spells out the merged {uuid_G0: handle, uuid_G1: handle, ...} dict + collective_rpc fan-out inside the vLLM server, and step (3) makes version-with-data atomicity explicit. Drop the "match slime's sglang_engine signature" framing. - vllm_engine.update_weights_from_tensor: collapse the long sglang-vs-vLLM compare block into a focused docstring describing what the POST does and why ipc_handles needs cloudpickle. Add a Chinese call-stack walkthrough (trainer → ★this method★ → server collective_rpc → per-TP worker receive_weights) and note that `node_rank != 0` is a dead branch since VLLMEngine pins node_rank=0 (see PR #48 review comment for the follow-up cleanup). - Hoist base64/cloudpickle imports to module scope so the hot path no longer pays the per-call import overhead. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> --------- Signed-off-by: aoshen02 <aoshen@inferact.ai> Signed-off-by: SamitHuang <285365963@qq.com> Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: SamitHuang <285365963@qq.com> Co-authored-by: Cursor <cursoragent@cursor.com>
* tests + CI: complete sglang→vllm rename across tests/ and .github/ Split from PR #18 (gcl/clean-sglang). One of 4 PRs splitting the original PR #18 by content area: docs (#38) / examples (#39) / **tests+CI** / core runtime. 42 files / +~750 / -~700. These are bundled in a single PR because the CI workflows reference test file names by string — splitting them would create a window where either tests are renamed but CI still points at the old names, or vice versa, breaking CI mid-roll. What this PR does: (A) tests/ (38 files): - Mechanical CLI-flag rename: --sglang-* → --vllm-* equivalents in all test scripts (matches the table now used in scripts/ and examples/). - Variable rename: SGLANG_ARGS → VLLM_ARGS where present. - 4 file renames (R086-R091, all >85% similarity): test_qwen2.5_0.5B_opd_sglang.py → test_qwen2.5_0.5B_opd_vllm.py test_qwen2.5_0.5B_sglang_config.py → test_qwen2.5_0.5B_vllm_config.py test_qwen2.5_0.5B_sglang_config_distributed.py → test_qwen2.5_0.5B_vllm_config_distributed.py test_sglang_config_mixed_offload.py → test_vllm_config_mixed_offload.py test_sglang_config_mixed_offload_ft.py → test_vllm_config_mixed_offload_ft.py tests/utils/test_sglang_config.py → tests/utils/test_vllm_config.py - 2 new tests for the IPC weight-transfer path landed in PR #18: tests/test_update_weight_from_tensor.py tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py (These are PR #22 / colocate-IPC test coverage; the production code the slim PR #18 ships will rely on the same code from PR #22.) (B) .github/ (4 files): - workflows/conda-ci.yml: container image lmsysorg/sglang → vime (inferactinc/public:vime-vllm-cu129-latest). - workflows/pr-test.yml + pr-test.yml.j2 (template): * Container images (slimerl/slime[-test]:latest → vime image) on every job that ran on the sglang-era base. * e2e-test-sglang-config job → e2e-test-vllm-config job (renamed label `run-ci-sglang-config` → `run-ci-vllm-config`; matrix `test_file` entries updated to point at the renamed test files in (A)). * e2e-test-megatron + e2e-test-image matrices: `_opd_sglang.py` entries → `_opd_vllm.py`. - ISSUE_TEMPLATE/bug_report.yml: drop the "SGLang version (if relevant):" environment field, add "vLLM version:" and "vllm-router version:" lines. (PR #36 already changed "CUDA/ROCm version" → "CUDA version" earlier; that change is preserved.) Sgl residue intentionally kept (4 hits — all anti-regression assertions that prove sglang code paths are gone, not residual references to bring back): - tests/test_update_weight_from_tensor.py:753 — comment "The vLLM IPC implementation must NOT contain sglang-style Gloo gather code". - tests/unit/backends/vllm_utils/test_arguments.py:233-237 — three assertions that --sglang-router-ip, --sglang-router-port, and sglang_router_ip are NOT present in the argument parser. Tests + CI must land together; splitting them risks a window where the CI matrix references test files by names that don't exist yet (or no longer exist). After this lands, the test_file string in CI matches the test files on disk. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com> * on_policy_distillation: port from SGLang to vLLM /v1/completions Follow-up on the test rename in this PR: test_qwen2.5_0.5B_opd_sglang.py → test_qwen2.5_0.5B_opd_vllm.py. The test only spawns a vLLM teacher and exercises the OPD pipeline; the real broken piece was slime/rollout/on_policy_distillation.py, which PR #18 left in SGLang request/response shape: request fields: "max_new_tokens": 0 (vLLM: "max_tokens") "return_logprob": True (sglang-only) "logprob_start_len": 0 (sglang-only) response parsing: reward["meta_info"]["input_token_logprobs"] (sglang shape) vLLM 0.21 supports the same workflow natively via `prompt_logprobs`: request to POST /v1/completions: { "model": <teacher>, "prompt_token_ids": sample.tokens, "max_tokens": 1, "temperature": 0, "prompt_logprobs": 1, "logprobs": 0, "skip_special_tokens": False, } response: response["choices"][0]["prompt_logprobs"] # list[dict[int, Logprob] | None] where Logprob is {"logprob": float, "rank": int, "decoded_token": str} References checked against vllm source: - reference/vllm/vllm/entrypoints/openai/completion/protocol.py:91 (request: prompt_logprobs: int | None) - reference/vllm/vllm/entrypoints/openai/completion/protocol.py:487 (response: prompt_logprobs: list[dict[int, Logprob] | None] | None) - reference/vllm/vllm/logprobs.py:13 (Logprob dataclass: logprob/rank/decoded_token) Implementation notes: 1. JSON serializes int dict keys as strings, so `_logprob_for_token` tries both `pos_entry.get(token_id)` and `pos_entry.get(str(token_id))`. 2. `pos_entry` is `None` at position 0 (no prior context) — handled explicitly. We also gracefully degrade if a token at position `i` is not in the top-1 logprob dict (falls back to 0.0, same as the prior sglang code would do). 3. The Logprob dataclass `decoded_token` field is unused; we only read `.logprob`. Both dict and `Logprob` shapes are accepted in case the server uses a flatter serialization toggle. 4. `args.opd_teacher_model` is the new model-name arg; falls back to `args.hf_checkpoint` if not set, mirroring how vime's other rollout paths derive the model name. Smoke-tested `_logprob_for_token` locally: - None entry → 0.0 - int key + dict value → logprob - str key (JSON shape) → logprob - missing token → 0.0 - flattened float value → float Also drops 3 lines from tests/unit/backends/vllm_utils/test_arguments.py: the `--sglang-router-ip`/`--sglang-router-port`/`sglang_router_ip` anti- regression assertions. Once the slim PR #18 lands and sglang is gone from the runtime, those assertions are vacuous; treating sglang as non-existent per the project policy. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com> * tests: drop duplicate smoke test updates from PR40 * test(update_weight_from_tensor): drop stale _apply_monkey_patch_torch_reductions patch The inner ``with patch(f"{MODULE_PATH}._apply_monkey_patch_torch_reductions"):`` context in _run_update suppressed a helper call that PR #48 has since deleted from update_weight_from_tensor.py (commit 39bf899 on aoshen/align-ipc-rpc-with-slime). After that PR lands the patched attribute won't exist and this line raises AttributeError. Remove it now so the test survives PR #48 merge. The ``sglang_mod.monkey_patch_torch_reductions = MagicMock()`` stub on the fake sglang module is intentionally kept: on this branch the production code still imports it via ``from ..sglang import monkey_patch_torch_reductions`` (both update_weight_from_tensor._apply_monkey_patch_torch_reductions on PR #40's view of main, and hf_weight_iterator_direct.py at module level). Removing the stub here would break the test on PR #40 alone; it can be dropped in a follow-up once PR #48 finishes removing every import site. Tests: ``tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py`` all 6 pass with this change applied to gcl/pr18-tests-ci HEAD. * tests: drop duplicate top-level test_update_weight_from_tensor.py The 786-line tests/test_update_weight_from_tensor.py is a stale rebase leftover from the original PR #18 branch — it predates the IPC test file PR #22 landed at the canonical unit-test path (tests/unit/backends/megatron_utils/update_weight/test_update_weight_from_tensor.py) and predates PR #48's single-RPC weight-version contract. Comparing the two: * Both stub sys.modules / torch.distributed at module import time, so having two files compounds the test-isolation issue Gemini raised (PR #40 comment #1). * Coverage overlaps materially (e.g. test_ipc_init_called_on_first_update_only ≈ test_ipc_init_runs_once — same invariant, different wording). * The nested file is up-to-date with PR #48's RPC contract (update_weights_from_tensor.remote(**fields, weight_version=...)); the top-level file still uses the pre-#48 lifecycle shape and does not exercise the coordinator slot fields. * The nested path matches repo convention: tests/unit/ for mock-only unit tests, tests/ top level for e2e scripts. Closes Gemini comment #1 on PR #40. Gemini comment #2 (the same stub pattern in the surviving nested file) is a pre-existing issue from PR #22 / #48 and out of scope for this rename PR — to be addressed in a follow-up that converts _install_stubs() to an autouse module-scoped fixture with save/restore. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com> * test(vllm_config): use real get_model_url default endpoint /inference/v1/generate get_model_url defaults to /inference/v1/generate (PR #18), not /v1/completions. Aligns this test with PR #18's test_vllm_config.py so the two PRs no longer conflict on this file and the assertion matches the actual runtime default. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * Drop on_policy_distillation.py from tests+CI PR (now owned by runtime PR #18) The OPD vLLM /v1/completions migration is a runtime change; it was folded into the core-runtime PR (#18). Restore this file to main here so the two PRs no longer overlap on it. #18 merges first, so this lands via #18. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * Drop unit-test files now owned by runtime PR #18 test_vllm_config.py + the plugin_contracts tests are coupled to #18's runtime rename (they import vllm_config / vllm_rollout, which #18 creates). They live in #18; remove them here so the two PRs don't overlap. #18 merges first. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test: restore vLLM rollout args dropped during sglang→vllm rename The mechanical sglang→vllm rename dropped several rollout knobs instead of mapping them to their vLLM equivalents, weakening CI coverage (cuda-graph capture caps, speculative decoding, expert parallel). Restore them using the mapping established by the converted production scripts on main (run-glm4.7-30B-A3B.sh / run-glm5-744B-A40B.sh), verified against vLLM AsyncEngineArgs: --sglang-cuda-graph-max-bs N -> --vllm-max-cudagraph-capture-size N --sglang-cuda-graph-bs a b c -> --vllm-cudagraph-capture-sizes a b c --sglang-ep-size N -> --vllm-enable-expert-parallel --sglang-speculative-* (eagle) -> --vllm-speculative-config '{"method":"eagle","num_speculative_tokens":K}' Also: - glm4.7 pd: fix --vllm-max-num-seqs (was 8, taken from cuda-graph-max-bs; --sglang-max-running-requests was 16) and split out cuda-graph capture. - fix sglang→rollout mis-renames in temp-file prefixes (→ vllm_*). - test_vllm_config: rename test_update_weights_default_true → test_update_weights_defaults_to_none (it asserts `is None`). Dropped sglang flags with no vLLM equivalent (enable-dp-lm-head, moe-dense-tp-size, watchdog-timeout, mamba-scheduler-strategy, disaggregation-transfer-backend, enable-metrics) stay dropped; PD KV-transfer is driven by --prefill-num-servers + the --vllm-config prefill/decode topology. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(plugin_contracts): migrate from sglang_rollout to vllm_rollout The three plugin-contract tests still imported slime.rollout.sglang_rollout and called install_stubs(with_sglang_router=True), but _shared.install_stubs already dropped that parameter — so all three failed at collection (TypeError: unexpected keyword 'with_sglang_router'). Complete the migration: - install_stubs(with_sglang_router=True, ...) -> install_stubs(...) - import generate_and_rm / generate_rollout from slime.rollout.vllm_rollout - default rollout/eval path string -> slime.rollout.vllm_rollout.generate_rollout (matches runtime default at slime/utils/arguments.py:233) - FakeGenerateState: sglang_enable_deterministic_inference -> vllm_enable_deterministic_inference, with group_sampling_seeds defaulting to None and gated on the flag (mirrors the already-migrated tests/unit/rollout/test_vllm_rollout.py). All 34 plugin-contract cases pass (were 3 collection errors before). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(update_weight_from_tensor): drop stale slime…megatron_utils.sglang mock The test pre-registered a sys.modules mock for slime.backends.megatron_utils.sglang (monkey_patch_torch_reductions), left over from when update_weight_from_tensor imported it. The module under test no longer imports that module (its real deps are get_gloo_group / HfWeightIteratorBase / update_weight_from_distributed), so the mock is dead. Removing it makes tests/ and .github/ fully sglang-free. Test still passes (7/7). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * [Clean] Remove SGLang runtime code Rebuilt against current main so the PR contains only the SGLang runtime removal -- the docs / tests-ci / examples / scripts / docker portions were split into separate PRs that have since merged. - Delete dead SGLang server/runtime code: sglang_utils/{arguments,sglang_engine}.py, rollout/sglang_rollout.py, the megatron_utils/sglang.py re-export shim, and all docker/**/sglang.patch files. - Rename the rollout config module sglang_utils/sglang_config.py -> vllm_utils/vllm_config.py (SglangConfig -> VllmConfig, _resolve_sglang_config -> _resolve_vllm_config, --sglang-config -> --vllm-config); inline the GPU_MEMORY_TYPE_* constants in rollout.py. - Add megatron_utils/fp8_helpers.py for the UE8M0 fp8 helpers formerly re-exported through the sglang shim; repoint quantizer_fp8 to it. - Swap sglang_router -> vllm_router in http_utils/wandb_utils; drop the dead sglang-router dependency from requirements.txt. - Finish the SGLang->vLLM rename in the runtime so it is internally consistent and matches the tests landing in the tests/CI PR: * router args --router-* -> --vllm-router-* (vllm_router_ip/port/timeout); * get_model_url reads vllm_model_routers (aligning with rollout.py); * --opd-type sglang -> vllm; engine_overrides rename; * sglang_enable_deterministic_inference -> vllm_enable_deterministic_inference, wired to a real --vllm-enable-deterministic-inference flag (exports VLLM_BATCH_INVARIANT=1); * consistent_hash session-id routing uses vllm-router's x-session-id header; * drop dead trace helper build_sglang_meta_trace_attrs; de-SGLang comments/docstrings. - Rename test_sglang_config.py -> test_vllm_config.py and de-SGLang the plugin-contract tests. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * Address review: finish de-SGLang + fold OPD/router-policy into runtime - naming: replace residual generic "rollout engine"/"engine"/"comm" wording with concrete vLLM (engine_overrides -> vllm_overrides; arguments help text; http_utils comments; rollout.py "inference workers"). sglang->vllm is correct, sglang->generic is not. - megatron_to_hf: drop the q_a_proj/kv_a_proj_with_mqa pairing + _cached_tensors global. That was sglang-only: sglang's loader torch.cat's both shards within a single load_weights call (needs them co-bucketed), whereas vLLM loads each shard independently via stacked_params_mapping into fused_qkv_a_proj. Also fix the misleading "merge into single fused name" comment. - docker/Dockerfile: remove now-dead sglang/sglang-router --no-deps stubs + the build-time `import sglang` smoke check (slime no longer imports sglang_router). - OPD: migrate on_policy_distillation.py teacher logprobs to vLLM /v1/completions (prompt_logprobs) instead of sglang return_logprob / meta_info.input_token_logprobs. - routing replay: register --vllm-router-policy (dest=router_policy) so the consistent_hash x-session-id session-affinity path is actually wired (was dead). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * Review follow-ups: mirror slime vllm_config parsing + restore vLLM process cleanup - vllm_config.from_yaml: drop the needless `models_raw` intermediate and iterate `data["vllm"]` directly, restoring the "Accept both server_groups / legacy engine_groups" comment -- mirrors slime's sglang_config.from_yaml line-for-line. - command_utils.execute_train: re-add a process kill for leftover rollout engines as `pkill -9 -f "vllm serve"` (the old `pkill -9 sglang` was dropped with no vLLM equivalent), so stale engines don't hold GPUs/ports across runs. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * Drop test changes from runtime PR; tests live in the tests+CI PR (#40) The plugin_contracts tests and the test_sglang_config -> test_vllm_config rename are coupled to the test/CI rename effort and are owned by #40. Restore them to main here so #18 is purely the SGLang runtime removal. #18 merges first; #40 rebases and re-lands the vLLM test versions. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fp8_helpers: copy SGLang verbatim (fix import crash); pin vLLM deep_gemm env - fp8_helpers.py: replace the bespoke rewrite with SGLang's exact implementations of quant_weight_ue8m0 / transform_scale_ue8m0 and their DeepGEMM helpers (per_block_cast_to_fp8, ceil_to_ue8m0, ceil_div, ceil_align, the torch-impl packer). deep_gemm is imported lazily inside the functions (as SGLang does), so module import no longer requires deep_gemm. This fixes the module-level `NameError: _get_tma_aligned_size` that crashed `import megatron_to_hf` on any deep_gemm image, and drops the invented sf-stride fixup block that was not in upstream. Only should_deepgemm_weight_requant_ue8m0 stays vLLM-adapted (is_deep_gemm_e8m0_used) since SGLang's reads SGLang-internal deep_gemm_wrapper. - vllm_engine.launch_server_process: set VLLM_USE_DEEP_GEMM=1 + VLLM_DEEP_GEMM_WARMUP=relax explicitly (setdefault) alongside VLLM_BATCH_INVARIANT, replacing SGLang's removed deep_gemm precompile/warmup envs. All vLLM engine env now lives in the subprocess env builder (single source of truth). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fp8_helpers: revert to vLLM impl + fix the import NameError; add vLLM trace attrs - fp8_helpers.py: keep the vLLM-based implementation (uses vllm.utils.deep_gemm, consistent with the vLLM runtime) rather than the SGLang verbatim copy. Fix the module-level crash: the `try` block referenced `_get_tma_aligned_size` before it was bound (the "pre-imported with fallback" import was never written), which raised NameError whenever deep_gemm imported successfully -- and NameError is not caught by `except ImportError`, so `import megatron_to_hf` crashed on any deep_gemm image. Replace the bogus self-assignment with the real import: `from vllm.utils.deep_gemm import get_tma_aligned_size as _get_tma_aligned_size`. - trace_utils/vllm_rollout: add build_vllm_meta_trace_attrs and attach finish_reason + token usage to the vllm_inference_generate span (mirrors SGLang's build_sglang_meta_trace_attrs; vLLM responses lack the pd_* timing, which lives in vLLM's own OTLP traces). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(opd): score teacher via /inference/v1/generate with prompt_logprobs Move the vllm OPD teacher path off the OpenAI /v1/completions endpoint onto vime's native /inference/v1/generate (the same endpoint the rollout engines use), and fix three latent issues: 1. model field: /inference/v1/generate takes `model` as OPTIONAL. Stop defaulting to args.hf_checkpoint (the *student* name, which mis-names a teacher!=student server). Add --opd-teacher-model; send `model` only when set, otherwise omit it (single-model teacher servers use their loaded model). 2. multimodal: the old code sent image_data to a token-only endpoint, which is invalid. Raise NotImplementedError until the /v1/chat/completions/render -> /inference/v1/generate flow is wired (mirrors slime.rollout.vllm_rollout.generate). 3. logprob robustness: read top-level GenerateResponse.prompt_logprobs, assert it is present and length-aligned with token_ids, assert the per-sample tensor covers response_length, and raise (not silently return 0.0) on a missing token logprob. vLLM always includes the actual prompt token in prompt_logprobs, so a miss is a real error. Alignment is unchanged (plp[i] <-> tokens[i], skip pos 0, take [-response_length:]). Follow-up (separate, in the tests PR): the OPD e2e test must launch a teacher that exposes /inference/v1/generate and point --rm-url at it. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * chore(clean-sglang): purge SGLang from tools, train scripts, and build infra tools/: drop dead `args.sglang_enable_ep_moe` shim (read nowhere); reword profile/replay helpers to vLLM and map analyzer hints to vLLM flags (--enforce-eager, --gpu-memory-utilization). train{,_async}.py: comments SGLang -> vLLM. build infra: remove build_conda.sh (SGLang-only conda path); drop the GB300 sgl-kernel install from the Dockerfile; delete docker/npu_patch/ wholesale. docker base image: bump to vLLM v0.22.0. justfile ARM recipes now pin the real multi-arch vLLM base images instead of the dead SGLANG_IMAGE_TAG/ ENABLE_SGLANG_PATCH build-args -- cu129-arm64 -> v0.22.0-cu129-ubuntu2404 (CUDA 12.9), cu13-arm64 -> v0.22.0-ubuntu2404 (the default-CUDA tag is already CUDA 13.0) + ENABLE_CUDA_13=1. vLLM tags are multi-arch manifests, so docker selects the arm64 image automatically on an ARM host. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * ci(clean-sglang): drop conda-build workflow (ran deleted build_conda.sh on SGLang image) The single build-conda job ran `bash build_conda.sh` (removed in the previous commit) inside an lmsysorg/sglang container. With the SGLang-only conda path gone, the whole workflow is dead. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * chore(clean-sglang): fix stale SGLang refs in docs/skills; tidy comments docs/conf.py: point the "edit on GitHub" links at vllm-project/vime instead of the inherited sgl-project.github.io repo. .claude/skills/*: update the dead `slime/rollout/sglang_rollout.py` references to `vllm_rollout.py` (the real default is slime.rollout.vllm_rollout.generate_rollout). justfile: drop the redundant BASE_IMAGE override on release-cu129-arm64 (it equalled the Dockerfile default; the multi-arch manifest already resolves arm64). train{,_async}.py: drop stray "the" in the W&B comment. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(tests): use method=mtp (not eagle) in vllm speculative config The migrated speculative configs pass no draft `model`, so method=eagle raises "num_speculative_tokens was provided but without speculative model" in vLLM's SpeculativeConfig. These models carry embedded MTP layers, so method=mtp is correct and unblocks the mimo MTP-only-grad test (#19). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * fix(cleanup): target renamed vLLM subprocesses in pkill so VRAM is freed vLLM's set_process_title() renames the VRAM-holding subprocesses (VLLM::EngineCore, VLLM::Worker_TP*, vllm::router), so their cmdline no longer contains "vllm serve". The previous `pkill -9 -f "vllm serve"` matched only the launcher and left engine/worker children holding GPU memory, leaking it into the next run — masked only by the indiscriminate `pkill -9 python`, which is unsafe on colocate/shared nodes. Match both the launcher and the renamed children with `pkill -9 -f '[v]llm serve|VLL[M]::'`; the [v]/[M] bracket trick keeps the pattern from matching pkill's own cmdline. This makes the broad python kill unnecessary, so its already-commented-out lines are removed. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * fix(speculative): use method=mtp (not eagle) for embedded-MTP models vLLM's SpeculativeConfig requires an explicit draft `model` for method=eagle; with only num_speculative_tokens set it raises "num_speculative_tokens was provided but without speculative model". The migrated configs in scripts/examples/docs pass no model, so they must use method=mtp, which reuses the target checkpoint's embedded MTP layer (DeepSeek-R1, GLM-4.x-MoE, MiMo, Qwen3-Next/3.5). The two docs examples that pass an explicit "model" are genuine eagle usage and are left unchanged. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * fix(vllm): launch each rollout engine with its ServerGroup's per-group TP launch_server_process / _init_normal derived tensor-parallel size and CUDA_VISIBLE_DEVICES from the global --rollout-num-gpus-per-engine, ignoring the per-engine num_gpus_per_engine already carried on the VLLMEngine actor. A ServerGroup configured with num_gpus_per_engine greater than the global flag (e.g. tp=2) therefore launched as tp=1, while the NCCL weight-sync rendezvous sized world_size from engine_gpu_counts (the per-group value). The two disagreed: the trainer waited for a rank the under-sized engine never started, so init_weight_transfer_engine hung for 300s ("3/4 clients joined") and the job failed. Honor the per-engine num_gpus_per_engine at launch, falling back to the global flag when unset (matches the SGLang path and PR #66's _compute_server_args). Verified on H200: tests/test_qwen2.5_0.5B_vllm_config_distributed now launches engine0 tp=2 / engine1 tp=1, update_weights completes in 1.1s (was a 301s timeout), and rollout+eval proceed. AI assistance (Claude Code) was used for this change. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(ckpt): add --dist-ckpt-optim-fully-reshardable for PAO+offload save/load test_qwen3_4B_ckpt.py uses precision-aware optimizer + cpu-offload (HybridDeviceOptimizer). Under the default dp_reshardable (bucket-centric) optimizer sharding, save/load produce unequal-length param_state lists, so dist-ckpt load fails with "Cannot merge two lists with different lengths (81 and 79)". fully_reshardable is model-centric and immune to bucket-layout changes. Verified on the r3 image (Megatron-LM 0.16.0rc0 @ 1dcf0da): save+load both succeed, and source review confirms master_param / step / HybridDeviceOptimizer sync are handled on this path. This is the flag described in PR #50 that was never actually merged. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> * refactor(router-args): hybrid naming — vllm_ for ip/port, bare router_ for timeout vllm-router's RouterArgs.from_cli_args only supports prefix "" or "router_" (never "vllm_router_"), and excludes host/port from its CLI via exclude_host_port=True. So: - --vllm-router-ip / --vllm-router-port keep the vllm_ prefix: RouterArgs does not own these CLI flags, vime does (populated via _start_router's manual router_args.host/port assignment), so the vllm_ prefix is free and marks them as vime-owned endpoint config. - --router-request-timeout-secs goes bare (dest router_request_timeout_secs): it is a genuine RouterArgs field, so it shares the --router-* namespace with policy / cache_threshold / retries / … and flows through from_cli_args like the other knobs. - --vllm-router-policy keeps dest=router_policy (unchanged). Also fixes conftest fixture to seed vllm_router_ip/port (was bare router_ip/port, which never matched the vllm_engine reader) and updates README/README_zh prose. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com> Co-authored-by: Canlin Guo <canlinguosdu@gmail.com>
…bject patch arguments.py (361→346 lines): - Import FlexibleArgumentParser from vllm.utils.argparse_utils; use it in vllm_parse_args() and get_vllm_cli_action_table() so vLLM's deprecated kwarg is handled natively on Python 3.12 without a shim - Remove _ARGPARSE_UNSUPPORTED_KWARGS + _strip_unsupported_argparse_kwargs - Remove import logging / logger (unused) reloadable_process_group.py: - Drop dist.gather_object monkey-patch (added by PR #22, never in slime; callers explicitly use all_gather_object to stay on the patched path) Architecture note: subprocess vllm serve kept intentionally — run_server() is not in vllm.__all__ and changes across minor versions; AReaL uses the same Popen pattern for the same reason. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
…bject patch arguments.py (361→346 lines): - Import FlexibleArgumentParser from vllm.utils.argparse_utils; use it in vllm_parse_args() and get_vllm_cli_action_table() so vLLM's deprecated kwarg is handled natively on Python 3.12 without a shim - Remove _ARGPARSE_UNSUPPORTED_KWARGS + _strip_unsupported_argparse_kwargs - Remove import logging / logger (unused) reloadable_process_group.py: - Drop dist.gather_object monkey-patch (added by PR #22, never in slime; callers explicitly use all_gather_object to stay on the patched path) Architecture note: subprocess vllm serve kept intentionally — run_server() is not in vllm.__all__ and changes across minor versions; AReaL uses the same Popen pattern for the same reason. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai>
* sync: complete slime #1920, #1967, #1985 — lint, fully_async, PYTHONUNBUFFERED Traced 3 individual diffs back to their source slime PRs (以点带面) and synced all remaining changes from each: slime #1985 (make tests shorter): - Wrap NamedTemporaryFile across 3 lines in test_vllm_config_mixed_offload_ft.py - Remove extra blank line in test_vllm_config_mixed_offload.py (parameter shortening already synced in vime PR #218) slime #1920 (move fully_async example to main codebase): - Rewrite README.md to match upstream (qwen2.5-0.5B, not qwen3-4b) - Add run-qwen2.5-0.5B-fully_async.sh with proper vLLM translations - Delete run-qwen3-4b-fully_async.sh (upstream removed it) slime #1967 (fix PYTHONBUFFERED typo): - Fix PYTHONBUFFERED=16 → PYTHONUNBUFFERED=1 in 3 scripts: run-glm4.7-30B-A3B.sh, run-glm4.7-355B-A32B.sh, run-minimax-m2.sh (command_utils.py already fixed in prior sync) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * fix: correct §2.4 flag translations in analyze_profile.py --enforce-eager → --vllm-enforce-eager --gpu-memory-utilization → --vllm-gpu-memory-utilization These are diagnostic hint strings, not CLI invocations, but should still use the canonical vime flag names (§2.4 translation rules). Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * fix: mirror slime underline + revert group_id comment to rollout_id - analyze_profile.py: match slime's 30-char underline (was 28) - run_qwen36_35b_a3b_swe_8nodes.sh: revert group_id→rollout_id in comment (partial sync of slime #2013, target commit 44d29ee5) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * refactor(arguments): use FlexibleArgumentParser; revert dist.gather_object patch arguments.py (361→346 lines): - Import FlexibleArgumentParser from vllm.utils.argparse_utils; use it in vllm_parse_args() and get_vllm_cli_action_table() so vLLM's deprecated kwarg is handled natively on Python 3.12 without a shim - Remove _ARGPARSE_UNSUPPORTED_KWARGS + _strip_unsupported_argparse_kwargs - Remove import logging / logger (unused) reloadable_process_group.py: - Drop dist.gather_object monkey-patch (added by PR #22, never in slime; callers explicitly use all_gather_object to stay on the patched path) Architecture note: subprocess vllm serve kept intentionally — run_server() is not in vllm.__all__ and changes across minor versions; AReaL uses the same Popen pattern for the same reason. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * ci: revert aoshen02 CI additions; align J2 template with slime Reverts PR #26 (pre-commit gate) + PR #110 (e2e-test-unit). Syncs from slime: opened/reopened trigger types, --pull=always, pip deps (requests ray safetensors), cpu-unittest rename. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * docs(docker): translate Chinese to English in README Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * fix(ci): stub vllm_router in plugin_contracts for cpu-unittest Mirrors slime's with_sglang_router stub pattern: add with_vllm_router kwarg to install_stubs() and pass it from test_plugin_generate_contracts. vllm_rollout.py imports vllm_router at module level; without the stub the cpu-unittest job fails with ModuleNotFoundError. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * fix(ci): add missing with_vllm_router=True stub to remaining plugin contracts test_plugin_rollout_contracts and test_plugin_path_loading_contracts both import vllm_rollout (which has bare `import vllm_router` at module level) but were not passing with_vllm_router=True to install_stubs — mirroring the same gap fixed in test_plugin_generate_contracts. Mirrors slime: all three tests pass with_sglang_router=True. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * docs(coding_agent_rl): align generate.py and README.md wording with slime - generate.py: drop backtick-wrapping around /inference/v1/generate in module docstring; collapse to one line matching slime style - README.md: condense rollout-max-*-len paragraph (remove verbose "sampling-params" / "generation length" verbiage, restore `max_tokens` inline like slime's `max_new_tokens` form) - README.md: trim vLLM response-structure detail (choices[0].token_ids / choices[0].logprobs.content[i].logprob) from token-out bullet — matches slime's abstraction level - README.md: add missing 3-line unit-test sentence after provenance paragraph (slime has it, vime was missing it) Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * refactor(arguments): remove dist_ckpt_optim_fully_reshardable warning block Not present in slime; drop to maintain mirror parity. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * refactor(rollout): remove redundant assertions and finalization re-assignments on_policy_distillation.py: drop two assertions not present in slime (len(plp)==len(sample.tokens) and len(t_log_prob)>=response_length). vllm_streaming_rollout.py: drop 9-line finalization block that re-set sample.tokens/response/response_length/rollout_log_probs/loss_mask after the streaming loop had already written the same values. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> * style: apply black formatting to fix pre-commit CI Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> Signed-off-by: aoshen02 <aoshen@inferact.ai> --------- Signed-off-by: aoshen02 <aoshen@inferact.ai> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

co-author: @SamitHuang
Purpose
Enable colocated weight synchronization between the Megatron trainer and vLLM rollout engines running on the same GPU(s), using CUDA IPC (Inter-Process Communication) via Ray instead of NCCL distributed broadcast. This avoids cross-node traffic and reduces weight sync latency when trainer and inference engine share the same physical GPUs.
What is Changed
New:
UpdateVLLMWeightFromTensor(slime/backends/megatron_utils/update_weight/update_weight_from_tensor_vllm.py)A new weight-update class following the vLLM RLHF IPC approach. It handles the full colocated sync lifecycle:
HfWeightIteratorBase.IPCWeightTransferEngine.trainer_send_weights(send_mode="ray"), creating a CUDA IPC handle per GPU.update_weights_from_distributed) is preserved unchanged.The per-
update_weightscall lifecycle is:Modified:
slime/backends/vllm_utils/vllm_engine.pyupdate_weights(update_info)— new public Ray-callable entry point. Sinceipc_handlesare Python callables (closures frommonkey_patch_torch_reductions) that cannot be JSON-serialized, they are serialized withcloudpickleand base64-encoded intoipc_handles_pickled, which the vLLMIPCWeightTransferUpdateInfoaccepts whenVLLM_ALLOW_INSECURE_SERIALIZATION=1is set.release_memory_occupation(level=1)— now accepts alevelparameter.level=0releases both KV cache and model weights (required before IPC tensor injection);level=1(default, unchanged) releases KV cache only.init_weight_transfer_engine(payload)— new method, posts to/init_weight_transfer_enginewith retry logic (3 attempts with back-off).start_weight_update(is_checkpoint_format)— new method, posts to/start_weight_updateto enter IPC weight-update mode.finish_weight_update()— new method, posts to/finish_weight_updateto exit IPC weight-update mode.colocate=True: automatically injects--weight-transfer-config '{"backend":"ipc"}'and--worker-extension-cls slime.backends.vllm_utils.vllm_worker_extension.vLLMColocateWorkerExtensioninto the vLLM serve command, unless the user has already overridden them.New:
slime/backends/vllm_utils/vllm_worker_extension.pyIntroduces
vLLMColocateWorkerExtension, passed tovllm servevia--worker-extension-cls. On instantiation inside each vLLM worker process, it applies_VLLMHijack.hijack(), which monkey-patchesIPCWeightTransferEngine.receive_weightsto callmonkey_patch_torch_reductions()before deserializing CUDA IPC handles. The patch is idempotent and applied automatically without requiring explicit patching from the trainer side.Modified:
slime/backends/megatron_utils/actor.pyMinor update to wire
UpdateVLLMWeightFromTensorinto the actor's weight-update dispatch.Test
A comprehensive unit test suite is added in
tests/test_update_weight_from_tensor_vllm.py:UpdateVLLMWeightFromTensoris instantiated via a helper that directly sets instance attributes, bypassing GPU-requiring initialization paths (HfWeightIteratorBase.create(), etc.).RecordingRemoteMethod/RecordingEngine/RecordingIPCEngineobjects, enabling assertions on call arguments without touching any CUDA primitives.release → init → start → send → finish → resume), and retry behavior oninit_weight_transfer_enginefailures.Result validate for run Qwen3-4B under 4 card (TP2, 4 vllm engine and 4 actor train)


