Chapter 27. Set Pool Values

To set a value to a pool, execute the following:

ceph osd pool set <pool-name> <key> <value>

You may set values for the following keys:

size

Description: Sets the number of replicas for objects in the pool. See Set the Number of Object Replicas_ for further details. Replicated pools only.
Type: Integer

min_size

Description: Sets the minimum number of replicas required for I/O. See Set the Number of Object Replicas_ for further details. Replicated pools only.
Type: Integer
Version: 0.54 and above

crash_replay_interval

Description: The number of seconds to allow clients to replay acknowledged, but uncommitted requests.
Type: Integer

pgp_num

Description: The effective number of placement groups to use when calculating data placement.
Type: Integer
Valid Range: Equal to or less than pg_num.

crush_ruleset

Description: The ruleset to use for mapping object placement in the cluster.
Type: Integer

hashpspool

hit_set_type

hit_set_count

Description: The number of hit sets to store for cache pools. The higher the number, the more RAM consumed by the ceph-osd daemon.
Type: Integer
Valid Range: 1. Agent doesn’t handle > 1 yet.

hit_set_period

Description: The duration of a hit set period in seconds for cache pools. The higher the number, the more RAM consumed by the ceph-osd daemon.
Type: Integer
Example: 3600 1hr

hit_set_fpp

cache_target_dirty_ratio

Description: The percentage of the cache pool containing modified (dirty) objects before the cache tiering agent will flush them to the backing storage pool.
Type: Double
Default: .4

cache_target_full_ratio

Description: The percentage of the cache pool containing unmodified (clean) objects before the cache tiering agent will evict them from the cache pool.
Type: Double
Default: .8

target_max_bytes

Description: Ceph will begin flushing or evicting objects when the max_bytes threshold is triggered.
Type: Integer
Example: 1000000000000 #1-TB

target_max_objects

Description: Ceph will begin flushing or evicting objects when the max_objects threshold is triggered.
Type: Integer
Example: 1000000 #1M objects

cache_min_flush_age

Description: The time (in seconds) before the cache tiering agent will flush an object from the cache pool to the storage pool.
Type: Integer
Example: 600 10min

cache_min_evict_age

Description: The time (in seconds) before the cache tiering agent will evict an object from the cache pool.
Type: Integer
Example: 1800 30min