[Hybrid] Fix and optimize block-aligned splitting in mamba cache align mode#33706
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vllm-bot merged 10 commits intovllm-project:mainfrom Feb 13, 2026
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[Hybrid] Fix and optimize block-aligned splitting in mamba cache align mode#33706vllm-bot merged 10 commits intovllm-project:mainfrom
vllm-bot merged 10 commits intovllm-project:mainfrom
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Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
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This pull request addresses an issue with block-aligned splitting in Mamba's cache align mode, which previously did not handle resumed requests correctly. The changes ensure that block-aligned splitting is performed for both new and resumed requests during the prefill phase. Additionally, the logic is optimized to handle prompt and output tokens separately for resumed requests, which should improve cache hit rates. The code has been refactored to introduce a helper function _mamba_compute_cache_pos for better clarity. The changes appear correct and well-implemented to solve the described problem.
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heheda12345
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Feb 4, 2026
This reverts commit c29650b. Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
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…gn mode (vllm-project#33706) Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com> Signed-off-by: Eldar Kurtic <research@neuralmagic.com>
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…gn mode (vllm-project#33706) Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
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…gn mode (vllm-project#33706) Signed-off-by: huanghaoyan.hhy <huanghaoyan.hhy@alibaba-inc.com>
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Purpose
Currently, block-aligned splitting is only executed during the prefill phase of new requests (
num_output_tokens == 0). It does not account for resumed requests. This leads to resumed requests being scheduled without block alignment, causing Mamba states to be stored in a non-aligned fashion. Consequently, incorrect states are retrieved during subsequent cache hits.Changes in this PR:
Optimize the logic to split prompt tokens and output tokens separately on block-aligned boundaries for resumed requests. This ensures that the Mamba states at the end of the prompt is cached, improving the cache hit rate during request replays.Removed for code simplicity.Test Plan
Test Result
Essential Elements of an Effective PR Description Checklist
supported_models.mdandexamplesfor a new model.