Shrink the receive read buffer from 16 MB to 64 KiB - #11
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The 16 MB read buffer dates from before record reassembly existed, when a read had to swallow a whole record or lose its tail. ReceiveLoop now accumulates across reads, so the read size only decides how many iterations a large payload takes; framing is unaffected at any size, which the reassembly test asserts down to a single byte per read. aznet's Read handles a caller buffer smaller than a frame by returning a partial copy and draining the remainder on the next call, so a small buffer costs extra copies, not correctness. The allocation is per handler, so the proxy was reserving 16 MB per connected agent, and the agent 16 MB for one transport.
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Last item from the deferred list in the stream-integrity round.
The 16 MB read buffer in
ReceiveLoopdates from before record reassembly existed, when a singleReadhad to swallow a whole record or lose its tail. Sinceaccnow reassembles across reads, the read size only decides how many iterations a large payload takes — framing is unaffected at any size, which the reassembly test already asserts down to one byte per read.aznet's
Readhandles a caller buffer smaller than a frame by copyingmin(frameLen, len(p))and draining the remainder on the next call, so a smaller buffer costs extra copies, never bytes.The allocation is per handler: the proxy was reserving 16 MB per connected agent.
Verified:
go build ./...,go vet ./...,go test ./... -race -count=1, and the wasm agent build.