| license | Apache-2.0 |
| name | database-connection-pool-manager |
| description | PgBouncer, connection optimization, and pooling strategies for database performance. Activate on: connection pool, PgBouncer, database connections, pool size, connection limit, Prisma pool, Drizzle pool. NOT for: query optimization (use data-warehouse-optimizer), database schema design (use dimensional-modeler). |
| allowed-tools | Read,Write,Edit,Bash(npm:*,npx:*,docker:*,psql:*) |
| category | Backend & Infrastructure |
| tags | ["database","connection-pool","pgbouncer","performance","postgres"] |
| pairs-with | [{"skill":"multi-tenant-architecture-expert","reason":"Multi-tenant apps require careful pool segmentation"},{"skill":"observability-apm-expert","reason":"Connection pool metrics are critical for performance monitoring"},{"skill":"data-warehouse-optimizer","reason":"Warehouse query patterns affect pool sizing"}] |
Database Connection Pool Manager
Optimize database connection pools for throughput, latency, and resource efficiency using PgBouncer, application-level poolers, and cloud-managed pools.
Activation Triggers
Activate on: "connection pool", "PgBouncer", "database connections", "pool size", "connection limit", "too many connections", "connection timeout", "Prisma pool", "Supabase pooler"
NOT for: SQL query optimization → data-warehouse-optimizer | Schema design → dimensional-modeler | ORM selection → api-architect
Quick Start
- Audit current connections —
SELECT count(*) FROM pg_stat_activity to understand baseline
- Choose pooling mode — transaction pooling (default), session pooling (for prepared statements)
- Size the pool — start with
connections = (cores * 2) + spindle_count per PostgreSQL docs
- Deploy pooler — PgBouncer sidecar or Supabase/Neon built-in pooler
- Monitor — track active/idle/waiting connections, query queue time
Core Capabilities
| Domain | Technologies |
|---|
| External Poolers | PgBouncer 1.23+, Odyssey, PgCat |
| Cloud Poolers | Supabase Supavisor, Neon pooler, RDS Proxy |
| App-Level | Prisma connection pool, Drizzle pool, node-postgres Pool |
| Monitoring | pg_stat_activity, PgBouncer SHOW commands, Prometheus |
| Databases | PostgreSQL 16+, MySQL 8.4+, CockroachDB |
Architecture Patterns
PgBouncer Transaction Pooling
App Instances (100 connections)
↓
PgBouncer (pool_mode = transaction)
max_client_conn = 200
default_pool_size = 20
reserve_pool_size = 5
↓
PostgreSQL (max_connections = 30)
Key: 200 app connections share 20 actual database connections. Each connection is released back to the pool at transaction end.
Pool Sizing Formula
Optimal pool size = ((core_count * 2) + effective_spindle_count)
Example (8-core server, SSD):
pool_size = (8 * 2) + 1 = 17
For serverless (many short-lived functions):
pgbouncer.default_pool_size = 20
pgbouncer.min_pool_size = 5
app.max_pool_size = 5 (per function instance)
total_functions * 5 <= pgbouncer.max_client_conn
