[Bug][Qwen3TTS][Streaming] remove dynamic initial chunk and only compute on initial request by JuanPZuluaga · Pull Request #1930 · vllm-project/vllm-omni

JuanPZuluaga · 2026-03-16T17:14:18Z

PLEASE FILL IN THE PR DESCRIPTION HERE ENSURING ALL CHECKLIST ITEMS (AT THE BOTTOM) HAVE BEEN CONSIDERED.

Purpose

The initial_chunk_size (IC) in talker2code2wav_async_chunk was recomputed on every call based on the current number of active requests. Under concurrency, active changes between steps as requests arrive and finish, causing the same request to get different IC values mid-flight.

the fix is to compute IC once per request on first call, cache in transfer_manager._cached_ic[request_id], reuse on all subsequent calls. The adaptive load sampling still happens at request start, it just doesn't shift mid-request.

Test Plan

Test Result

Audios generated under different conditions:

text: Hello, welcome to the voice synthesis test.

c4_ic2.wav
c4_ic_default.wav
non_stream_pcm.wav
non_stream_wav.wav

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(Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model. Please run mkdocs serve to sync the documentation editions to ./docs.
(Optional) Release notes update. If your change is user-facing, please update the release notes draft.

BEFORE SUBMITTING, PLEASE READ https://github.com/vllm-project/vllm-omni/blob/main/CONTRIBUTING.md (anything written below this line will be removed by GitHub Actions)

Signed-off-by: JuanPZuluaga <juanz9312@gmail.com>

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chatgpt-codex-connector · 2026-03-16T17:18:19Z

+            cached_ic = getattr(self, "_cached_ic", None)
+            if cached_ic is not None:
+                cached_ic.pop(request_id, None)


Evict cached initial chunk size during adapter cleanup

The new _cached_ic state is only cleared in the is_finished branch here, but requests can also terminate through OmniChunkTransferAdapter.cleanup() (for example, error/failed-load paths in omni_generation_scheduler) without necessarily executing this send-loop branch. That leaves per-request cache entries resident indefinitely and can apply stale IC values if request IDs are reused; please also remove _cached_ic[external_req_id] in cleanup() alongside code_prompt_token_ids and request_payload.

Useful? React with 👍 / 👎.

Sy0307 · 2026-03-16T17:37:25Z

Totally good. Notice _cached_ic should be cleaned up after request.

Signed-off-by: JuanPZuluaga <juanz9312@gmail.com>

linyueqian · 2026-03-16T18:35:14Z

i tested on my end and it seems that problem is solved. @Sy0307 @jwd-dev please double check.

linyueqian

LGTM

JuanPZuluaga · 2026-03-16T18:36:38Z

integrated last comment @Sy0307 @linyueqian

Sy0307 · 2026-03-16T19:21:18Z

LGTM. Tests sound good without any weird noise ;)

…ute on initial request (vllm-project#1930) Signed-off-by: JuanPZuluaga <juanz9312@gmail.com>

…ute on initial request (vllm-project#1930) Signed-off-by: JuanPZuluaga <juanz9312@gmail.com> Signed-off-by: yiliu30 <yi4.liu@intel.com>

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Changes: - Bug fix: [bugfix] /chat/completion doesn't read extra_body for diffusion model ### vllm-omni-perf - Source: [PR #2042](vllm-project/vllm-omni#2042) - [bugfix] /chat/completion doesn't read extra_body for diffusion model - Changes: - Bug fix: [bugfix] /chat/completion doesn't read extra_body for diffusion model ### vllm-omni-contrib - Source: [PR #2038](vllm-project/vllm-omni#2038) - [Doc] Update docs and dockerfiles for rebase of vllm v0.18.0 ### vllm-omni-serving - Source: [PR #2037](vllm-project/vllm-omni#2037) - [Rebase] Rebase to vllm v0.18.0 ### vllm-omni-contrib - Source: [PR #2037](vllm-project/vllm-omni#2037) - [Rebase] Rebase to vllm v0.18.0 ### vllm-omni-api - Source: [PR #2037](vllm-project/vllm-omni#2037) - [Rebase] Rebase to vllm v0.18.0 ### vllm-omni-cicd - Source: [PR #2037](vllm-project/vllm-omni#2037) - [Rebase] Rebase to vllm v0.18.0 ### vllm-omni-cicd - Source: [PR #2032](vllm-project/vllm-omni#2032) - [CI] Change Bagel online test environment variable `VLLM_TEST_CLEAN_GPU_MEMORY` to `0` ### vllm-omni-cicd - Source: [PR #2031](vllm-project/vllm-omni#2031) - [CI] Fix test. - Changes: - Bug fix: [CI] Fix test. ### vllm-omni-cicd - Source: [PR #2017](vllm-project/vllm-omni#2017) - [CI] [ROCm] Setup `test-ready.yml` and `test-merge.yml` ### vllm-omni-cicd - Source: [PR #2014](vllm-project/vllm-omni#2014) - [Test] Implement mock HTTP request handling in benchmark CLI tests ### vllm-omni-perf - Source: [PR #2014](vllm-project/vllm-omni#2014) - [Test] Implement mock HTTP request handling in benchmark CLI tests ### vllm-omni-serving - Source: [PR #2012](vllm-project/vllm-omni#2012) - [Fixbug][Perf] Qwen3-omni: code predictor with re-prefill + SDPA and eliminate decode hot-path CPU round-trips - Changes: - Bug fix: [Fixbug][Perf] Qwen3-omni: code predictor with re-prefill + SDPA and eliminate decode hot-path CPU round-trips ### vllm-omni-image-gen - Source: [PR #2012](vllm-project/vllm-omni#2012) - [Fixbug][Perf] Qwen3-omni: code predictor with re-prefill + SDPA and eliminate decode hot-path CPU round-trips - Changes: - Bug fix: [Fixbug][Perf] Qwen3-omni: code predictor with re-prefill + SDPA and eliminate decode hot-path CPU round-trips ### vllm-omni-perf - Source: [PR #2012](vllm-project/vllm-omni#2012) - [Fixbug][Perf] Qwen3-omni: code predictor with re-prefill + SDPA and eliminate decode hot-path CPU round-trips - Changes: - Bug fix: [Fixbug][Perf] Qwen3-omni: code predictor with re-prefill + SDPA and eliminate decode hot-path CPU round-trips ### vllm-omni-serving - Source: [PR #2009](vllm-project/vllm-omni#2009) - [Bugfix] revert PR#1758 which introduced the accuracy problem of qwen3-omni - Changes: - Bug fix: [Bugfix] revert PR#1758 which introduced the accuracy problem of qwen3-omni ### vllm-omni-image-gen - Source: [PR #2007](vllm-project/vllm-omni#2007) - [Bugfix]Fix bug of online server can not return mutli images - Changes: - Bug fix: [Bugfix]Fix bug of online server can not return mutli images - Additions: - Qwen-Image-Layered - Qwen-Image-Layered - Qwen-Image-Layered ### vllm-omni-api - Source: [PR #2007](vllm-project/vllm-omni#2007) - [Bugfix]Fix bug of online server can not return mutli images - Changes: - Bug fix: [Bugfix]Fix bug of online server can not return mutli images ### vllm-omni-cicd - Source: [PR #1998](vllm-project/vllm-omni#1998) - [CI] Split BAGEL tests into dummy/real weight tiers (L2/L3) ### vllm-omni-serving - Source: [PR #1985](vllm-project/vllm-omni#1985) - [Perf] [Qwen3-TTS] Keep audio_codes and last_talker_hidden on GPU to eliminate per-step sync stalls - Changes: - Performance improvement: [Perf] [Qwen3-TTS] Keep audio_codes and last_talker_hidden on GPU to eliminate per-step sync stalls ### vllm-omni-audio-tts - Source: [PR #1985](vllm-project/vllm-omni#1985) - [Perf] [Qwen3-TTS] Keep audio_codes and last_talker_hidden on GPU to eliminate per-step sync stalls - Changes: - Performance improvement: [Perf] [Qwen3-TTS] Keep audio_codes and last_talker_hidden on GPU to eliminate per-step sync stalls ### vllm-omni-perf - Source: [PR #1985](vllm-project/vllm-omni#1985) - [Perf] [Qwen3-TTS] Keep audio_codes and last_talker_hidden on GPU to eliminate per-step sync stalls - Changes: - Performance improvement: [Perf] [Qwen3-TTS] Keep audio_codes and last_talker_hidden on GPU to eliminate per-step sync stalls ### vllm-omni-serving - Source: [PR #1984](vllm-project/vllm-omni#1984) - [CI] [ROCm] Bugfix device environment issue - Changes: - Bug fix: [CI] [ROCm] Bugfix device environment issue ### vllm-omni-api - Source: [PR #1984](vllm-project/vllm-omni#1984) - [CI] [ROCm] Bugfix device environment issue - Changes: - Bug fix: [CI] [ROCm] Bugfix device environment issue ### vllm-omni-serving - Source: [PR #1982](vllm-project/vllm-omni#1982) - [Fix] Fix slow hasattr in CUDAGraphWrapper.__getattr__ - Changes: - Bug fix: [Fix] Fix slow hasattr in CUDAGraphWrapper.__getattr__ ### vllm-omni-cicd - Source: [PR #1982](vllm-project/vllm-omni#1982) - [Fix] Fix slow hasattr in CUDAGraphWrapper.__getattr__ - Changes: - Bug fix: [Fix] Fix slow hasattr in CUDAGraphWrapper.__getattr__ ### vllm-omni-api - 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Fix Base voice clone streaming quality and stop-token crash - Changes: - Bug fix: Fix Base voice clone streaming quality and stop-token crash ### vllm-omni-cicd - Source: [PR #1938](vllm-project/vllm-omni#1938) - [Test] L4 complete diffusion feature test for Bagel models - Changes: - New feature: [Test] L4 complete diffusion feature test for Bagel models ### vllm-omni-perf - Source: [PR #1938](vllm-project/vllm-omni#1938) - [Test] L4 complete diffusion feature test for Bagel models - Changes: - New feature: [Test] L4 complete diffusion feature test for Bagel models ### vllm-omni-perf - Source: [PR #1934](vllm-project/vllm-omni#1934) - Fix OmniGen2 transformer config loading for HF models - Changes: - Bug fix: Fix OmniGen2 transformer config loading for HF models ### vllm-omni-audio-tts - Source: [PR #1930](vllm-project/vllm-omni#1930) - [Bug][Qwen3TTS][Streaming] remove dynamic initial chunk and only compute on initial request ### vllm-omni-perf - Source: [PR #1930](vllm-project/vllm-omni#1930) - [Bug][Qwen3TTS][Streaming] remove dynamic initial chunk and only compute on initial request ### vllm-omni-audio-tts - Source: [PR #1926](vllm-project/vllm-omni#1926) - [Misc] removed qwen3_tts.py as it is out-dated ### vllm-omni-contrib - Source: [PR #1920](vllm-project/vllm-omni#1920) - [Docs] Add Wan2.1-T2V as supported video generation models - Changes: - New feature: [Docs] Add Wan2.1-T2V as supported video generation models ### vllm-omni-video-gen - Source: [PR #1915](vllm-project/vllm-omni#1915) - [Bugfix] fix helios video generate use cpu device - Changes: - Bug fix: [Bugfix] fix helios video generate use cpu device ### vllm-omni-perf - Source: [PR #1915](vllm-project/vllm-omni#1915) - [Bugfix] fix helios video generate use cpu device - Changes: - Bug fix: [Bugfix] fix helios video generate use cpu device ### vllm-omni-audio-tts - Source: [PR #1913](vllm-project/vllm-omni#1913) - [Optim][Qwen3TTS][CodePredictor] support torch.compile with reduce-overhead and dynamic False ### vllm-omni-perf - 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[Feat] support HSDP for Flux family - Changes: - New feature: [Feat] support HSDP for Flux family ### vllm-omni-distributed - Source: [PR #1898](vllm-project/vllm-omni#1898) - [Feature]: Remove some useless `hf_overrides` in yaml - Changes: - New feature: [Feature]: Remove some useless `hf_overrides` in yaml ### vllm-omni-quantization - Source: [PR #1898](vllm-project/vllm-omni#1898) - [Feature]: Remove some useless `hf_overrides` in yaml - Changes: - New feature: [Feature]: Remove some useless `hf_overrides` in yaml ### vllm-omni-cicd - Source: [PR #1898](vllm-project/vllm-omni#1898) - [Feature]: Remove some useless `hf_overrides` in yaml - Changes: - New feature: [Feature]: Remove some useless `hf_overrides` in yaml ### vllm-omni-perf - Source: [PR #1898](vllm-project/vllm-omni#1898) - [Feature]: Remove some useless `hf_overrides` in yaml - Changes: - New feature: [Feature]: Remove some useless `hf_overrides` in yaml ### vllm-omni-contrib - Source: [PR #1890](vllm-project/vllm-omni#1890) - [NPU] Upgrade to v0.17.0 ### vllm-omni-contrib - Source: [PR #1889](vllm-project/vllm-omni#1889) - Add `Governance` section - Changes: - New feature: Add `Governance` section ### vllm-omni-distributed - Source: [PR #1881](vllm-project/vllm-omni#1881) - [Feat] Support T5 Tensor Parallelism - Changes: - New feature: [Feat] Support T5 Tensor Parallelism ### vllm-omni-cicd - Source: [PR #1881](vllm-project/vllm-omni#1881) - [Feat] Support T5 Tensor Parallelism - Changes: - New feature: [Feat] Support T5 Tensor Parallelism

Fix test assertions and mocks that fell out of sync with source code changes in qwen3_tts.py across PRs vllm-project#1930, vllm-project#1852, and vllm-project#2104. - test_flush_on_finish: `finished` is now a plain bool, not a tensor; remove `.item()` call - test_ic_load_change_mid_request: IC is cached per request since vllm-project#1930; update expected emission frames to match current logic - test_non_async_processor_prepends_ref_code_and_sets_trim_context: add missing `finished=True` and `token_ids` to mock (required since vllm-project#2104) - test_non_async_processor_filters_out_of_range_codec_values: same fix Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Signed-off-by: linyueqian <linyueqian@outlook.com>

remove dynamic initial chunk and only compute on initial request

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Signed-off-by: JuanPZuluaga <juanz9312@gmail.com>

JuanPZuluaga requested a review from hsliuustc0106 as a code owner March 16, 2026 17:14

JuanPZuluaga mentioned this pull request Mar 16, 2026

[Bug]: Qwen 3 TTS Generating Incorrect Audio #1861

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add cleanup cached_ic

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Signed-off-by: JuanPZuluaga <juanz9312@gmail.com>

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linyueqian approved these changes Mar 16, 2026

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Merge branch 'main' into bugfix/non-dynamic-first-chunk

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Sy0307 mentioned this pull request Mar 16, 2026

Unstable inference when using vllm with cloning QwenLM/Qwen3-TTS#263

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linyueqian merged commit cf328eb into vllm-project:main Mar 16, 2026
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JuanPZuluaga deleted the bugfix/non-dynamic-first-chunk branch March 16, 2026 19:27

linyueqian mentioned this pull request Mar 16, 2026

[Bug]: QWEN3-TTS: noise insertion at the very front of voice #1707

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tangbinh pushed a commit to tangbinh/vllm-omni that referenced this pull request Mar 18, 2026

[Bug][Qwen3TTS][Streaming] remove dynamic initial chunk and only comp…

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…ute on initial request (vllm-project#1930) Signed-off-by: JuanPZuluaga <juanz9312@gmail.com>

linyueqian mentioned this pull request Mar 31, 2026

[Test] Fix 4 broken Qwen3-TTS async chunk unit tests #2351

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[Bug][Qwen3TTS][Streaming] remove dynamic initial chunk and only compute on initial request#1930

[Bug][Qwen3TTS][Streaming] remove dynamic initial chunk and only compute on initial request#1930
linyueqian merged 3 commits intovllm-project:mainfrom
JuanPZuluaga:bugfix/non-dynamic-first-chunk

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