add prefix warmup to prime cache before server startup - #9
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new --prefix-warmup-file flag runs chat warmup requests before serve_http; aborts startup on failure
Tushar-ml
marked this pull request as ready for review
June 3, 2026 12:18
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Adds
--prefix-warmup-file: runs chat warmup requests through the engine before/healthis exposed, to prime the prefix/KV cache and absorb one-time JIT/CUDA-graphcosts (pod warmup). Warmup goes through the normal chat path (template/tokenization match
real traffic). Fatal on failure.
Test Plan
gemma-4-31B-FP8, 100 cold-start requests, 10k input (7k shared prefix) / 50 output, with
vs without
--prefix-warmup-file.Test Result
Warmup runs before
/health(verified in logs); steady-state unchanged; startup tail removed.