dozzle/.claude/agent-memory/go-perf-reviewer/MEMORY.md

Go Performance Reviewer Memory

Hot Paths Identified

• Stats processing pipeline: ContainerStatsListener.enrich() -> channel -> Manager.processStatEvents() -> processStatEvent(). Runs continuously for every container stat tick (~1/sec per container).
• Log processing pipeline: ContainerLogListener -> logChannel (buffered 1000) -> Manager.processLogEvents() -> processLogEvent(). Every log line from matched containers flows here.
• Both pipelines do expr.Run() per subscription per event -- compiled programs are cached but still run per-event.

Architecture Notes

• ContainerStore.SubscribeStats and SubscribeEvents both call statsCollector.Start/Stop -- multiple subscribers share the same collector. Stop-on-cancel can interfere across subscribers.
• xsync.Map (from puzpuzpuz/xsync/v4) used extensively for concurrent maps. No built-in TTL/eviction.
• ContainerStatEvent carries full Container + Host structs by value through channels. Container is ~200+ bytes (strings, map, RingBuffer pointer, times).
• TTL caches in both listeners (cachedContainerInfo) lack eviction -- grow unboundedly with container churn.

Existing Patterns

• Semaphore-based concurrency limiting: sendSem (weighted 5) for notification dispatch, maxFetchParallelism (30) for container fetching.
• Lazy stats collection: stats collector starts on first subscriber, stops when last unsubscribes (but the multi-subscriber Stop race exists).
• sync.Pool not currently used in notification/stats paths.
• Cooldown tracking via xsync.Map[string, time.Time] per subscription -- also no eviction.

Key File Paths

• internal/container/container_store.go -- Container store with stats collector lifecycle
• internal/notification/processing.go -- Log + stat event processing (hot path)
• internal/notification/stats_listener.go -- Stats subscription and enrichment
• internal/notification/log_listener.go -- Log stream management
• internal/notification/manager.go -- Subscription CRUD and listener orchestration
• internal/notification/types.go -- Subscription matching (expr evaluation)