Perf: reduce per-exchange allocations on HTTP/1.1 hot path#631
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Skips the per-exchange x-fluxzy-live-edit header scan when not running under Fluxzy Desktop, removing a LINQ allocation and full header walk from the HTTP/1.1 hot path.
Replace List<IDisposable> + MemoryPool<char>.Shared with two inline char[] slots backed by ArrayPool<char>.Shared (plus lazy overflow List). Saves a List allocation per scope and the IMemoryOwner wrapper per rent on the HTTP/1.1 hot path.
RequestHeader.InitSettings and ResponseHeader's constructor plus ReadKeepAliveSettings used First/Any/LastOrDefault on the indexer, each allocating a yield-return iterator per call. Added TryGetFirstHeader, TryGetLastHeader, HasHeaderValueEqualsAny, and HasHeaderValueContains helpers on Header that iterate the backing List directly with its struct enumerator, and rewrote the callers accordingly.
This was referenced Apr 20, 2026
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Summary
Three small allocation cuts on the HTTP/1.1 MITM path:
x-fluxzy-live-editheader scan behind theFluxzyDesktopVersionenv var (exposed asFluxzySharedSetting.LiveEditEnabled). Standalone fluxzy no longer walks every request's headers looking for a desktop-only debug flag.ExchangeScopenow uses two inlinechar[]?slots plus a lazy overflow list, renting directly fromArrayPool<char>.Shared. Drops the unconditionalList<IDisposable>allocation and theIMemoryOwnerwrapper thatMemoryPool<char>.Shared.Rentreturns per header buffer.TryGetFirstHeader,TryGetLastHeader,HasHeaderValueEqualsAny, andHasHeaderValueContainshelpers onHeaderthat iterate the backingList<HeaderField>via its struct enumerator. RewroteRequestHeader.InitSettings, theResponseHeaderconstructors, andReadKeepAliveSettingsto use them, removing the yield-return iterator allocations from eachFirst/Any/LastOrDefaultcall.Targeting the
UseProxy=True, ServeH2=False, ResponseBodyLength=0row inProxyThroughputBenchmark(~7.7 µs, ~12.6 KB/op).