[V1][Metrics] Add TTFT and TPOT histograms #12530
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Compute these intervals on the API server side as EngineCoreOutputs are processed. The OutputProcessor needs to track per-request arrival times and the generation timestamp of the most recent token generation. Prefill intervals are calculated when the first EngineCoreOutput is received, indicating prefill completion. The histogram buckets match the v0 implementation, but they should probably be improved in future. Signed-off-by: Mark McLoughlin <[email protected]>
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DarkLight1337,
robertgshaw2-redhat,
simon-mo,
WoosukKwon,
njhill,
ywang96,
comaniac and
alexm-redhat
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| @@ -48,6 +52,8 @@ def update_from_output(self, output: "EngineCoreOutput", | |||
| return | |||
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| num_new_generation_tokens = len(output.new_token_ids) | |||
| now = time.time() | |||
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I have seen mixed use of time.time() and time.monotonic() - I think we should standardize on one or the other so we don't have a footgun down the road
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Yes!
I had initially changed to time.monotonic() but I backed it out because it looks like arrival_time being wall-clock time is part of the public API, so not something I wanted to rush into.
I'll make sure to do it or capture it as a TODO/FIXME before I wrap this up 👍
robertgshaw2-redhat
added
the
ready
Signed-off-by: Mark McLoughlin <[email protected]>
Follow on from #12516, part of #10582
Compute these intervals on the API server side as EngineCoreOutputs are processed.
The OutputProcessor needs to track per-request arrival times and the generation timestamp of the most recent token generation.
Prefill intervals are calculated when the first EngineCoreOutput is received, indicating prefill completion.
The histogram buckets match the v0 implementation, but they should probably be improved in future.