Chapter 27. Set Pool Values

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

Description

Set/Unset HASHPSPOOL flag on a given pool.

Type

Integer

Valid Range

1 sets flag, 0 unsets flag

Version

Version 0.48 Argonaut and above.

hit_set_type

Description

Enables hit set tracking for cache pools.

Type

String

Valid Settings

bloom, explicit_hash, explicit_object

Default

bloom. Other values are for testing.

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

Description

The false positive probability for the bloom hit set type.

Type

Double

Valid Range

0.0 - 1.0

Default

0.05

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