projectionValuesEqual took a Uint8List (how a bytea column arrives) down
its List branch and compared it byte by byte, and tryUuidValue parsed
every value as a UUID by throwing and catching an error when it was none.
Each byte of a payload thus cost a thrown TypeError, about 18 µs: two
payloads of 2 KB took 36 ms to compare. A sync whose projection loaded a
few thousand rows with payloads kept the server's isolate busy for
minutes, during which it answered no other request and the client's
method stream timed out, so the client sent the same changes again.
Byte values are now compared as bytes, and tryUuidValue only parses what
can hold a UUID (a UuidValue, 16 bytes, a 36-character string), returning
null for anything else without throwing. A UUID compares with its string
and its bytes as before. Longer byte values are no longer read as the
UUID of their first 16 bytes, which made canonicalProjectionValue group
payloads with the same beginning together.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MMm7usAo6q9ZZRoPkWjoxi
