[MISC] Dump model runner inputs when crashing

[comaniac]

To better reproduce the model runner crashing due to illegal memory access and possibly other errors, this PR introduces a utility that dumps model runner inputs when crashing. Since the model runner inputs may be long, I dumped them using pickle for now. Any suggestions or better ideas are welcome.

cc @robertgshaw2-neuralmagic @simon-mo @DarkLight1337

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[DarkLight1337]

Can we add instructions in the GitHub issues template so users can share their logs upon encountering such errors?

[comaniac]

Can we add instructions in the GitHub issues template so users can share their logs upon encountering such errors?

Good point. Will do

[youkaichao]

do we need to add a flag for this? looks like some debugging feature that can also be added in https://docs.vllm.ai/en/latest/getting_started/debugging.html

[robertgshaw2-redhat]

do we need to add a flag for this? looks like some debugging feature that can also be added in https://docs.vllm.ai/en/latest/getting_started/debugging.html

The goal is to be able to get logs from production usage to help track down hard to replicate bugs (like illegal mem access in prefix caching). So having a flag defeats the purpose

[youkaichao]

makes sense then. please ignore my comment.

[comaniac]

@DarkLight1337 added to issue template. PTAL.

[comaniac]

It should be fine as we never load it automatically? But yeah you may get virus if someone post a malicious pickle file to an issue...