What Is Shared Buffers?
Shared buffers are PostgreSQL’s internal memory cache for storing frequently accessed disk blocks. The shared_buffers parameter determines its size and is critical for tuning performance.
Why It Matters for PostgreSQL Performance
In PostgreSQL performance work, Shared Buffers affects throughput, latency, or operational reliability depending on workload and configuration.
Practical Benchmarking Context
When benchmarking with pgbench, track how Shared Buffers changes behavior across scale factor, client concurrency, and storage conditions.
Use this term together with workload shape, concurrency level, and scale factor when interpreting pgbench outputs. Isolated values can be misleading without full run context.
Example
Recommendation: 25–40% of total system memory.