Pools

The Ceph Object Gateway uses several pools for its various storage needs,which are listed in the Zone object (see radosgw-admin zone get). Asingle zone named default is created automatically with pool namesstarting with default.rgw., but a Multisite Configuration will havemultiple zones.

Tuning

When radosgw first tries to operate on a zone pool that does notexist, it will create that pool with the default values fromosd pool default pg num and osd pool default pgp num. These defaultsare sufficient for some pools, but others (especially those listed inplacement_pools for the bucket index and data) will require additionaltuning. We recommend using the Ceph Placement Group’s per PoolCalculator to calculate a suitable number ofplacement groups for these pools. SeePoolsfor details on pool creation.

Pool Namespaces

New in version Luminous.

Pool names particular to a zone follow the naming convention{zone-name}.pool-name. For example, a zone named us-east willhave the following pools:

• .rgw.root

• us-east.rgw.control

• us-east.rgw.meta

• us-east.rgw.log

• us-east.rgw.buckets.index

• us-east.rgw.buckets.data

The zone definitions list several more pools than that, but many of thoseare consolidated through the use of rados namespaces. For example, all ofthe following pool entries use namespaces of the us-east.rgw.meta pool:

"user_keys_pool": "us-east.rgw.meta:users.keys",
"user_email_pool": "us-east.rgw.meta:users.email",
"user_swift_pool": "us-east.rgw.meta:users.swift",
"user_uid_pool": "us-east.rgw.meta:users.uid",