[BugFix] Fix incremental detokenization perf issue#16963
[BugFix] Fix incremental detokenization perf issue#16963WoosukKwon merged 1 commit intovllm-project:mainfrom
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max was meant to be min - could cause O(n^2) blowup in pathological cases Signed-off-by: Nick Hill <nhill@redhat.com>
njhill
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WoosukKwon,
alexm-redhat,
comaniac,
robertgshaw2-redhat and
ywang96
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| prompt_len = len(prompt_suffix) | ||
| if prompt_len > 4: | ||
| for i in range(4, max(prompt_len + 1, 32)): | ||
| for i in range(4, min(prompt_len + 1, 24)): |
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Where does 24 come from? Can we use smaller numbers like 5?
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It's to try to find a small suffix to start from, or else it has to loop over the entire prompt below decoding the tokens one-by-one, which could be very long.
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So, does it mean we can't use smaller numbers?
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LGTM. Thanks for the fix! The performance looks normal after this PR:
============ Serving Benchmark Result ============
Successful requests: 100
Benchmark duration (s): 45.27
Total input tokens: 1000000
Total generated tokens: 20000
Request throughput (req/s): 2.21
Output token throughput (tok/s): 441.79
Total Token throughput (tok/s): 22531.15
---------------Time to First Token----------------
Mean TTFT (ms): 974.65
Median TTFT (ms): 413.66
P99 TTFT (ms): 2323.33
-----Time per Output Token (excl. 1st token)------
Mean TPOT (ms): 66.89
Median TPOT (ms): 77.80
P99 TPOT (ms): 83.48
---------------Inter-token Latency----------------
Mean ITL (ms): 66.89
Median ITL (ms): 27.12
P99 ITL (ms): 246.34
==================================================
Signed-off-by: Nick Hill <nhill@redhat.com> Signed-off-by: Frieda (Jingying) Huang <jingyingfhuang@gmail.com>
Signed-off-by: Nick Hill <nhill@redhat.com>
Signed-off-by: Nick Hill <nhill@redhat.com>
Signed-off-by: Nick Hill <nhill@redhat.com> Signed-off-by: Agata Dobrzyniewicz <adobrzyniewicz@habana.ai>
Signed-off-by: Nick Hill <nhill@redhat.com> Signed-off-by: Mu Huai <tianbowen.tbw@antgroup.com>
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maxwas meant to bemin- could cause O(n^2) blowup in pathological cases