Unlocking high-performance PostgreSQL with key memory optimizations
2 days ago
- #PostgreSQL
- #Database Optimization
- #Performance Tuning
- PostgreSQL performance optimization involves understanding settings like shared_buffers and work_mem.
- shared_buffers is a critical memory region for caching data, reducing disk I/O, and improving performance.
- Default shared_buffers is 128MB, but 20-25% of total RAM is recommended for dedicated servers.
- Too large shared_buffers can compete with OS cache and increase checkpoint pressure.
- Cache hit ratio and query-level analysis help determine optimal shared_buffers size.
- work_mem controls memory for operations like sorting and joins, and is per operation, not per session.
- Default work_mem is 4MB, but analytical queries may need more to avoid disk spills.
- work_mem can multiply across parallel workers and concurrent queries, risking OOM errors.
- Tuning work_mem involves monitoring temp file usage and disk spills in query plans.
- Conservative defaults, real metrics, and selective tuning are key to PostgreSQL optimization.