PostgreSQL — Benchmarks¶

Scope

PostgreSQL performance metrics, pgbench results, scaling characteristics, and comparison baselines.

pgbench Results (Standard Benchmark)¶

Hardware	Clients	TPS (read-write)	TPS (read-only)	Latency P99
4 vCPU, 16Gi, SSD	16	2,500-4,000	15,000-25,000	5-10ms
8 vCPU, 32Gi, NVMe	32	8,000-15,000	50,000-80,000	2-5ms
16 vCPU, 64Gi, NVMe	64	20,000-35,000	100,000-150,000	1-3ms
32 vCPU, 128Gi, NVMe	128	40,000-60,000	200,000-300,000	1-2ms

Operation	B-tree	Hash	GIN	GiST	BRIN
Point lookup	~0.1ms	~0.05ms	N/A	~0.5ms	~1ms
Range scan	~1ms	N/A	~5ms	~2ms	~0.5ms
Insert overhead	Low	Low	High	Medium	Very low
Storage per row	8-16 bytes	4-8 bytes	Variable	Variable	~1 byte

Connection Count	Without PgBouncer	With PgBouncer	Notes
50	100% baseline	100%	No difference
200	85-90%	98%	PgBouncer multiplexes
500	60-70%	95%	Memory pressure without pooler
1,000	30-40%	90%	Context switching kills perf
5,000	Fails (OOM)	85%	Must use connection pooling

Storage Type	WAL Write Throughput	fsync Latency	Notes
HDD	50-100 MB/s	5-20ms	Not recommended for production
SATA SSD	200-500 MB/s	0.5-2ms	Acceptable for small deployments
NVMe SSD	1-3 GB/s	0.05-0.2ms	Recommended for production

Scenario	Replication Lag	Throughput	Notes
Async, same DC	< 10ms	Near line-rate	Default config
Async, cross-DC	10-100ms	Network limited	WAN bandwidth matters
Sync, same DC	< 1ms	70-80% of standalone	Commit must wait for replica
Sync, cross-DC	10-50ms	20-40% of standalone	Not recommended for write-heavy

Dimension	Soft Limit	Hard Limit	Notes
Database size	10TB (comfortable)	100TB+	Needs partitioning beyond 10TB
Table size	1TB	32TB	Partition large tables
Rows per table	1 billion	No hard limit	Performance degrades with bloat
Columns per table	250	1,600	TOAST for wide rows
Indexes per table	20	No limit	Each index adds write overhead
Concurrent connections	200-500	10,000+ (with pooler)	Use PgBouncer