Every boost had its own fragment, nested inside the message fragment that
already holds it. With a cold cache, a read and a write per boost plus a
read_multi and a write_multi per message: a room page of 40 messages with
120 boosts takes ~410 ms instead of ~290 ms. Redis runs without persistence
(config/redis.conf), so every page is cold after a restart.
A boost touches its message, so adding or removing one rewrites the message
fragment anyway. The inner fragments only paid off when a message with many
boosts was drawn again, and there they hid a lookup per booster. The boosters
are now loaded with the boosts, one query per message.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0142qgjggdJ2KDdGk7RF9Xm9
Marcello Costagliola
Kevin McConnell