Placement group count

The number of placement groups (PGs) in a pool plays a significant role in how a cluster peers, distributes data, and rebalances.

Small clusters do not see as many performance improvements compared to large clusters by increasing the number of placement groups. However, clusters that have many pools accessing the same OSDs might need to carefully consider PG count so that Ceph OSDs use resources efficiently.

Note: Use 100–200 placement group replicas per OSD.