pgstress

README

pgstress

pgstress is a small CLI for opening many concurrent PostgreSQL connections and keeping them alive. It is useful for testing how a live PostgreSQL instance behaves under sustained connection pressure, including observing whether the database server restarts when Cloud SQL instance storage is increased.

Build

From the repository root:

go build ./cmd/pgstress

Run

./cmd/pgstress -host <host> -port <port> -user <user> -db <database> -connections 200

Flags

• -host : PostgreSQL host (required)
• -port : PostgreSQL port (default: 5432)
• -user : PostgreSQL user (required)
• -password : Password (optional when ~/.pgpass matches)
• -db : Database name (default: postgres)
• -sslmode : SSL mode (default: disable)
• -connections : Number of concurrent connections to open (required)
• -keepalive : Interval between SELECT 1 keepalive queries (default: 15s)
• -restart-check : Interval for checking pg_postmaster_start_time() (default: 30s)
• -duration : Run duration; use 0 to run until interrupted (default: 0)
• -connect-timeout : Timeout for initial connection attempts (default: 10s)
• -verbose : Print worker-level events
• -h : Print help

Example

./cmd/pgstress -host mycloudsql.example.com -port 5432 -user postgres -db postgres -connections 250 -keepalive 15s -restart-check 30s

Notes

• If -password is omitted, pgstress will attempt to read credentials from ~/.pgpass.
• Restart detection is performed by polling pg_postmaster_start_time() on each active connection.
• Use CTRL+C to stop the load test and print a final summary.