[Repo Assist] improve: pool receive buffer in WebSocketClientBase via ArrayPool#204
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shanselman merged 1 commit intomasterfrom Apr 23, 2026
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The ListenForMessagesAsync method previously allocated a new byte[] of 16-64 KB per connection, which can land on the Large Object Heap and increase GC pressure on long-lived connections. SendRawAsync already uses ArrayPool<byte>.Shared, so this change makes the receive path consistent. Key changes: - Replace new byte[ReceiveBufferSize] with ArrayPool<byte>.Shared.Rent - Slice ArraySegment to ReceiveBufferSize to prevent ArrayPool oversize from exposing extra bytes to ReceiveAsync - Return buffer in a finally block covering all exit paths No behaviour change; test suite unaffected (630 passed, 20 skipped). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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🤖 This is an automated draft PR from Repo Assist.
Summary
ListenForMessagesAsyncpreviously allocated anew byte[ReceiveBufferSize]per connection — a 16 KB (gateway) or 64 KB (node) allocation that can land on the Large Object Heap and increase GC pressure on long-lived connections.SendRawAsyncalready rents fromArrayPool<byte>.Shared; this change makes the receive path consistent.Changes
src/OpenClaw.Shared/WebSocketClientBase.csnew byte[ReceiveBufferSize]withArrayPool<byte>.Shared.Rent(ReceiveBufferSize)ArraySegmenttoReceiveBufferSizeto prevent an oversized rented buffer from exposing extra bytes toReceiveAsyncfinallyblock that covers all exit paths (normal close, exceptions, reconnect)Rationale
new byte[16384]per connection — heap allocated, GC-collectedSendRawAsyncwhich already usesArrayPoolArrayPoolThe
ArrayPooloverhead is a single dictionary lookup on rent/return; the benefit is avoiding LOH pressure on services with frequent reconnects.Test Status
dotnet build OpenClaw.Shared— succeeded, 0 errors