Ceph — Benchmarks
Scope
Performance characteristics, scaling limits, and resource consumption for Ceph.
RADOS Bench Results
| Operation |
3 OSD (HDD) |
3 OSD (SSD) |
12 OSD (NVMe) |
| Seq Write |
300-500 MB/s |
1-2 GB/s |
5-10 GB/s |
| Seq Read |
400-600 MB/s |
1.5-3 GB/s |
8-15 GB/s |
| Random 4K Write |
500-1,000 IOPS |
10k-30k IOPS |
100k+ IOPS |
| Random 4K Read |
1,000-2,000 IOPS |
20k-50k IOPS |
200k+ IOPS |
| Block Size |
Throughput |
IOPS |
Latency (P99) |
| 4K random |
N/A |
10k-50k |
1-5ms |
| 64K sequential |
500MB-2GB/s |
N/A |
2-10ms |
| 1M sequential |
1-5 GB/s |
N/A |
5-20ms |
Scaling Limits
| Dimension |
Limit |
Notes |
| OSDs per cluster |
10,000+ |
Tested by CERN |
| Total capacity |
Exabytes |
Linear scaling |
| Pools |
64 (default pg_num) |
Tune pg_num |
| PGs per OSD |
100-200 (recommended) |
Performance degrades beyond 300 |
| Objects per PG |
Millions |
No hard limit |