Writer.drain: coalesce 1-byte splat through a stack buffer#32
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Each call to Connection.writeAll emits a fresh TLS record (header + AEAD nonce + auth tag), so the previous loop (one writeAll per splat repetition) produced one record per byte for the common 1-byte pattern case. A 1 MiB splat became one million tiny records which is roughly three orders of magnitude slower than necessary. This change switches on pattern.len to handle the 1-byte case which mirrors std.Io.Writer's Hashing and Allocating drains.
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Nice, thanks. How did you run into this? |
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Was using this to spin up a small https server to stress test an http client (for Tuple). Was using splatByteAll to write some of the server responses. |
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Each call to Connection.writeAll emits a fresh TLS record (header + AEAD nonce + auth tag), so the previous loop (one writeAll per splat repetition) produced one record per byte for the common 1-byte pattern case. A 1 MiB splat became one million tiny records which is roughly three orders of magnitude slower than necessary.
This change switches on pattern.len to handle the 1-byte case which mirrors std.Io.Writer's Hashing and Allocating drains.