PgDog vs PgDoorman

PgDog is a PostgreSQL connection pooler, load balancer, and database sharder designed to scale databases without application changes. It multiplexes many application connections across fewer PostgreSQL server connections and supports SET, LISTEN/NOTIFY, and advisory locks. Read queries can be distributed across replicas while writes go to the primary, with health checks and failover detection. Sharding keys guide query routing; queries without a key can run across databases in parallel. Cross-shard transactions use PostgreSQL prepared transactions and two-phase commit, with automatic rollback on errors. PgDog can copy data and stream row changes to another database without pausing query traffic. Deployment options include Kubernetes Helm, Docker, AWS ECS Terraform, pre-built binaries, and source. Releases include Linux arm64 and amd64, Apple Silicon Mac, and Debian packages; the macOS binary is unsigned. The project is free and open source under AGPL-3.0, and documentation says internal use does not require sharing source code. Enterprise support includes architecture reviews, a dedicated Slack channel, and an SLA promising a response within 15 minutes.

PgDoorman is a free, open-source, self-hosted PostgreSQL connection pooler written in Rust. It is described as a drop-in replacement for PgBouncer and Odyssey, and supports PostgreSQL 10 and newer on Linux or macOS. Listed capabilities include connection pooling, load balancing, and automatic failover; query routing is not supported. The pool coordinator enforces per-database connection caps and can reclaim idle capacity from pools with spare connections. Patroni-assisted fallback can direct new connections to another live cluster member during a switchover. Monitoring includes a Prometheus endpoint and an optional local diagnostic console for pool, latency, error, query, log, CPU, and memory information. Authentication includes MD5 or SCRAM passthrough, auth_query, PAM, JWT, Talos JWT, and pg_hba.conf rules. TLS is supported for client and backend connections. It can be built from source, installed from packages, or downloaded as a binary.