pg_ash v1 - Active Session History for PostgreSQL

pg_ash samples `pg_stat_activity` once per second via `pg_cron`, stores encoded snapshots in partitioned tables, and provides 32 SQL functions for wait event analysis.

Pure SQL + PL/pgSQL. No C extension, no `shared_preload_libraries`, no restart required. Works anywhere `pg_cron` runs — managed providers (RDS, Cloud SQL, AlloyDB, Azure Database for PostgreSQL, Supabase, etc.), self-managed, Kubernetes, or any other deployment.

Storage: ~100-200 bytes per sample, ~30 MiB/day with `TRUNCATE`-based partition rotation (zero bloat).

Analysis functions include top waits, per-query wait profiles, wait event drill-down, time-range investigation, and timeline visualization. Functions are designed to chain naturally for iterative root cause analysis — by a human in psql or by AI tools such as Claude Code, OpenCode, or Codex.

PostgreSQL 14-18. Apache 2.0. CI tested.

[https://github.com/NikolayS/pg_ash](https://github.com/NikolayS/pg_ash)