[Bugfix] Fix MQLLMEngine hanging
#9973
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robertgshaw2-neuralmagic
requested review from
njhill,
comaniac and
youkaichao
| def run_mp_engine(engine_args: AsyncEngineArgs, usage_context: UsageContext, | ||
| ipc_path: str): | ||
| ipc_path: str, engine_alive): |
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add type annotation for the engine_alive variable?
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thanks for the fix! I'm not familiar with this code though, would be better to get reviews from @njhill
why is that the case? |
I spent an hour or so reading around on the internet, but I could not find anything conclusive. This did solve the issue I was seeing with the hanging though. @russellb - do you have any experience with this? |
not off the top of my head, but I'm happy to take a look today! |
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going to merge to fix the bug while we look into why |
did you have an easy way to reproduce it? I just tried to reproduce it by forcing LLMEngine.init to fail, but that didn't do it. |
I cannot quite determine the conditions in which |
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This git hash VLLM_USE_V1=1 vllm serve Qwen/Qwen2-0.5B-Instruct |
Signed-off-by: [email protected] <[email protected]> Signed-off-by: Linkun Chen <[email protected]>
Signed-off-by: [email protected] <[email protected]> Signed-off-by: Richard Liu <[email protected]>
Signed-off-by: [email protected] <[email protected]>
Signed-off-by: [email protected] <[email protected]> Signed-off-by: Loc Huynh <[email protected]>
Signed-off-by: [email protected] <[email protected]> Signed-off-by: Sumit Dubey <[email protected]>
Signed-off-by: [email protected] <[email protected]> Signed-off-by: Maxime Fournioux <[email protected]>
Signed-off-by: [email protected] <[email protected]> Signed-off-by: Tyler Michael Smith <[email protected]>
During the startup of the api server the setup function is called multiple times (every 5s). So the longer the longer the startup time (generally for larger models) the more consumers are contending for the output. This can then lead to race condition where the order of the answer token is wrong. Introduce here: vllm-project#9973 References: vllm-project#10376 vllm-project#10589 vllm-project#10782 Signed-off-by: Jannis Schönleber <[email protected]>
During the startup of the api server the setup function is called multiple times (every 5s). So the longer the longer the startup time (generally for larger models) the more consumers are contending for the output. This can then lead to race condition where the order of the answer token is wrong. Introduce here: vllm-project#9973 References: vllm-project#10376 vllm-project#10589 vllm-project#10782 Signed-off-by: Jannis Schönleber <[email protected]>
During the startup of the api server the setup function is called multiple times (every 5s). So the longer the longer the startup time (generally for larger models) the more consumers are contending for the output. This can then lead to race condition where the order of the answer token is wrong. Introduce here: vllm-project#9973 References: vllm-project#10376 vllm-project#10589 vllm-project#10782 Signed-off-by: Jannis Schönleber <[email protected]>
During the startup of the api server the setup function is called multiple times (every 5s). So the longer the longer the startup time (generally for larger models) the more consumers are contending for the output. This can then lead to race condition where the order of the answer token is wrong. Introduce here: vllm-project#9973 References: vllm-project#10376 vllm-project#10589 vllm-project#10782 Signed-off-by: Jannis Schönleber <[email protected]>
During the startup of the api server the setup function is called multiple times (every 5s). So the longer the longer the startup time (generally for larger models) the more consumers are contending for the output. This can then lead to race condition where the order of the answer token is wrong. Introduce here: vllm-project#9973 References: vllm-project#10376 vllm-project#10589 vllm-project#10782 Signed-off-by: Jannis Schönleber <[email protected]>
SUMMARY:
MQLLMEngineClientcan hang if theMQLLMEnginecrashes duringLLMEngine.__init__. Previously, we checked if the processis_alive, but if an exception is raised in theMQLLMEnginethe process can sometimes still reportis_alive=True.MQLLMEngineloop in a try...catch. We update the shared variable if an exception occurs and also log the exception. This ensures that the error will always be logged and the client can then check the shared variable and cleanly shut downBEFORE SUBMITTING, PLEASE READ THE CHECKLIST BELOW AND FILL IN THE DESCRIPTION ABOVE
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