perf(ext/node): flush-free header fast path in HTTP parser#33351
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When no prior kOnHeaders flush occurred (all headers fit in the current parser.execute batch and total stayed under MAX_HEADER_PAIRS), pass accumulated headers and url directly to parserOnHeadersComplete as the 3rd/5th args, skipping the kOnHeaders JS call. The slow path (flush via kOnHeaders + pass undefined) is retained for chunked-across-packets or >MAX_HEADER_PAIRS cases.
bartlomieju
approved these changes
Apr 22, 2026
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When no prior kOnHeaders flush occurred (all headers fit in the current parser.execute batch and total stayed under MAX_HEADER_PAIRS), pass accumulated headers and url directly to parserOnHeadersComplete as the 3rd/5th args, skipping the kOnHeaders JS call. The slow path (flush via kOnHeaders + pass undefined) is retained for chunked-across-packets or >MAX_HEADER_PAIRS cases.
This mimics node, and improves throughput by about 4% on hello world
Disclosure: used claude