- DB client: configure connection pool (max=20, idle_timeout=30s, connect_timeout=5s)
- DB schema: add missing indexes for auth sessions, accounts, conversations, agent_logs
- DB schema: promote preferences(user_id,key) to UNIQUE index for ON CONFLICT upsert
- Drizzle migration: 0003_p8003_perf_indexes.sql
- preferences.service: replace 2-query SELECT+INSERT/UPDATE with single-round-trip upsert
- conversations repo: add ORDER BY + LIMIT to findAll (200) and findMessages (500)
- session-gc.service: make onModuleInit fire-and-forget (removes cold-start TTFB block)
- next.config.ts: enable compress, productionBrowserSourceMaps:false, image avif/webp
- docs/PERFORMANCE.md: full profiling report and change impact notes
Implements three-tier garbage collection for agent sessions:
- SessionGCService.collect() for immediate per-session cleanup on destroySession()
- SessionGCService.sweepOrphans() for daily cron sweep of orphaned Valkey keys
- SessionGCService.fullCollect() for cold-start aggressive cleanup via OnModuleInit
- /gc slash command wired into CommandExecutorService + registered in CommandRegistryService
- SESSION_GC_CRON (daily 4am) added to CronService
- GCModule provides Valkey (ioredis via @mosaic/queue) and is imported by AgentModule, LogModule, CommandsModule, AppModule
- 8 Vitest unit tests covering all three GC tiers
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>