legacy: allow build-time override of watchdog timeout constants#678
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dmvevents wants to merge 1 commit into
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legacy: allow build-time override of watchdog timeout constants#678dmvevents wants to merge 1 commit into
dmvevents wants to merge 1 commit into
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Wrap LEGACY_NUM_CPU_TIMEOUT_SECS / LEGACY_NUM_TIMEOUT_CYCLES in #ifndef so integrators can raise them via compile flags without patching sources. Motivation: on first run, frameworks that JIT-compile their expert GEMMs (e.g. SGLang's DeepGEMM warmup, 10-20 min cold) hold some ranks inside dispatch while peers finish compiling. The hardcoded 100 s watchdog then kills the run with 'DeepEP error: timeout (dispatch CPU)' even though no communication fault exists. Measured on 2x p5en.48xlarge (H200, EFA): raising the constant to 1800 s rides out the warmup and the same workload completes; defaults are unchanged for everyone else. Signed-off-by: Anton Alexander <dmvevents@gmail.com>
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July 20, 2026 14:57
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Summary
Wraps
LEGACY_NUM_CPU_TIMEOUT_SECS/LEGACY_NUM_TIMEOUT_CYCLESin#ifndefso integrators can raise the watchdog at build time (e.g.-DLEGACY_NUM_CPU_TIMEOUT_SECS=1800) without patching sources. Defaults unchanged.Motivation
On first run, frameworks that JIT-compile their expert GEMMs hold some ranks inside dispatch while peers finish compiling. Concretely: SGLang's DeepGEMM warmup (10–20 min cold, per its own log banner) exceeds the hardcoded 100 s watchdog, which then kills the run with
DeepEP error: timeout (dispatch CPU)although no communication fault exists.Measured on 2× p5en.48xlarge (H200, 16 EFA NICs, EP16, Qwen3-30B-A3B-FP8, SGLang 0.5.5.post3): with the constant raised to 1800 s the identical workload completes and serves; write-up with numbers: https://dmvevents.github.io/deepep-efa-guidance/sections/08-v1-nvshmem-backend.html
Notes
deep_ep.Buffer) path where the constant lives; happy to extend the same guard to the EPv2 tree if wanted.#ifndefis the minimal non-breaking step.