.. describe:: hashpspool
- Set/Unset HASHPSPOOL flag on a given pool.
-
+ :Description: Sets and unsets the HASHPSPOOL flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
.. describe:: nodelete
- Set/Unset NODELETE flag on a given pool.
-
+ :Description: Sets and unsets the NODELETE flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
:Version: Version ``FIXME``
.. describe:: nopgchange
- :Description: Set/Unset NOPGCHANGE flag on a given pool.
+ :Description: Sets and unsets the NOPGCHANGE flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
:Version: Version ``FIXME``
.. describe:: nosizechange
- Set/Unset NOSIZECHANGE flag on a given pool.
-
+ :Description: Sets and unsets the NOSIZECHANGE flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
:Version: Version ``FIXME``
.. describe:: bulk
- Set/Unset bulk flag on a given pool.
-
+ :Description: Sets and unsets the bulk flag on a given pool.
:Type: Boolean
:Valid Range: true/1 sets flag, false/0 unsets flag
.. describe:: write_fadvise_dontneed
- Set/Unset WRITE_FADVISE_DONTNEED flag on a given pool.
-
+ :Description: Sets and unsets the WRITE_FADVISE_DONTNEED flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
.. describe:: noscrub
- Set/Unset NOSCRUB flag on a given pool.
-
+ :Description: Sets and unsets the NOSCRUB flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
.. describe:: nodeep-scrub
- Set/Unset NODEEP_SCRUB flag on a given pool.
-
+ :Description: Sets and unsets the NODEEP_SCRUB flag on a given pool.
:Type: Integer
:Valid Range: 1 sets flag, 0 unsets flag
.. describe:: hit_set_type
- Enables hit set tracking for cache pools.
- See `Bloom Filter`_ for additional information.
-
+ :Description: Enables HitSet tracking for cache pools.
+ For additional information, see `Bloom Filter`_.
:Type: String
:Valid Settings: ``bloom``, ``explicit_hash``, ``explicit_object``
:Default: ``bloom``. Other values are for testing.
.. describe:: hit_set_count
- The number of hit sets to store for cache pools. The higher
- the number, the more RAM consumed by the ``ceph-osd`` daemon.
-
+ :Description: Determines the number of HitSets to store for cache pools. The
+ higher the value, the more RAM is consumed by the ``ceph-osd``
+ daemon.
:Type: Integer
:Valid Range: ``1``. Agent doesn't handle > 1 yet.
.. describe:: hit_set_period
- 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.
-
+ :Description: Determines the duration of a HitSet period (in seconds) for
+ cache pools. The higher the value, the more RAM is consumed
+ by the ``ceph-osd`` daemon.
:Type: Integer
- :Example: ``3600`` 1hr
+ :Example: ``3600`` (3600 seconds: one hour)
.. _hit_set_fpp:
.. describe:: hit_set_fpp
- The false positive probability for the ``bloom`` hit set type.
- See `Bloom Filter`_ for additional information.
-
+ :Description: Determines the probability of false positives for the
+ ``bloom`` HitSet type. For additional information, see `Bloom
+ Filter`_.
:Type: Double
:Valid Range: 0.0 - 1.0
:Default: ``0.05``
.. describe:: cache_target_dirty_ratio
- The percentage of the cache pool containing modified (dirty)
- objects before the cache tiering agent will flush them to the
- backing storage pool.
-
+ :Description: Sets a flush threshold for the percentage of the cache pool
+ containing modified (dirty) objects. When this threshold is
+ reached, the cache-tiering agent will flush these objects to
+ the backing storage pool.
:Type: Double
:Default: ``.4``
.. _cache_target_dirty_high_ratio:
.. describe:: cache_target_dirty_high_ratio
-
- The percentage of the cache pool containing modified (dirty)
- objects before the cache tiering agent will flush them to the
- backing storage pool with a higher speed.
-
+
+ :Description: Sets a flush threshold for the percentage of the cache pool
+ containing modified (dirty) objects. When this threshold is
+ reached, the cache-tiering agent will flush these objects to
+ the backing storage pool with a higher speed (as compared with
+ ``cache_target_dirty_ratio``).
:Type: Double
:Default: ``.6``
.. _cache_target_full_ratio:
.. describe:: cache_target_full_ratio
-
- The percentage of the cache pool containing unmodified (clean)
- objects before the cache tiering agent will evict them from the
- cache pool.
+
+ :Description: Sets an eviction threshold for the percentage of the cache
+ pool containing unmodified (clean) objects. When this
+ threshold is reached, the cache-tiering agent will evict
+ these objects from the cache pool.
:Type: Double
:Default: ``.8``
.. _target_max_bytes:
.. describe:: target_max_bytes
-
- Ceph will begin flushing or evicting objects when the
- ``max_bytes`` threshold is triggered.
-
+
+ :Description: Ceph will begin flushing or evicting objects when the
+ ``max_bytes`` threshold is triggered.
:Type: Integer
:Example: ``1000000000000`` #1-TB
.. _target_max_objects:
.. describe:: target_max_objects
-
- Ceph will begin flushing or evicting objects when the
- ``max_objects`` threshold is triggered.
-
+
+ :Description: Ceph will begin flushing or evicting objects when the
+ ``max_objects`` threshold is triggered.
:Type: Integer
:Example: ``1000000`` #1M objects
.. describe:: hit_set_grade_decay_rate
-
- Temperature decay rate between two successive hit_sets
-
+
+ :Description: Sets the temperature decay rate between two successive
+ HitSets.
:Type: Integer
:Valid Range: 0 - 100
:Default: ``20``
.. describe:: hit_set_search_last_n
-
- Count at most N appearance in hit_sets for temperature calculation
-
+
+ :Description: Count at most N appearances in HitSets. Used for temperature
+ calculation.
:Type: Integer
:Valid Range: 0 - hit_set_count
:Default: ``1``
.. _cache_min_flush_age:
.. describe:: cache_min_flush_age
-
- The time (in seconds) before the cache tiering agent will flush
- an object from the cache pool to the storage pool.
-
+
+ :Description: Sets the time (in seconds) before the cache-tiering agent
+ flushes an object from the cache pool to the storage pool.
:Type: Integer
- :Example: ``600`` 10min
+ :Example: ``600`` (600 seconds: ten minutes)
.. _cache_min_evict_age:
.. describe:: cache_min_evict_age
-
- The time (in seconds) before the cache tiering agent will evict
- an object from the cache pool.
-
+
+ :Description: Sets the time (in seconds) before the cache-tiering agent
+ evicts an object from the cache pool.
:Type: Integer
- :Example: ``1800`` 30min
+ :Example: ``1800`` (1800 seconds: thirty minutes)
.. _fast_read:
.. describe:: fast_read
-
- On Erasure Coding pool, if this flag is turned on, the read request
- would issue sub reads to all shards, and waits until it receives enough
- shards to decode to serve the client. In the case of jerasure and isa
- erasure plugins, once the first K replies return, client's request is
- served immediately using the data decoded from these replies. This
- helps to tradeoff some resources for better performance. Currently this
- flag is only supported for Erasure Coding pool.
-
- :Type: Boolean
- :Defaults: ``0``
+
+ :Description: For erasure-coded pools, if this flag is turned ``on``, the
+ read request issues "sub reads" to all shards, and then waits
+ until it receives enough shards to decode before it serves
+ the client. If *jerasure* or *isa* erasure plugins are in
+ use, then after the first *K* replies have returned, the
+ client's request is served immediately using the data decoded
+ from these replies. This approach sacrifices resources in
+ exchange for better performance. This flag is supported only
+ for erasure-coded pools. :Type: Boolean :Defaults: ``0``
.. _scrub_min_interval:
projects / ceph.git / commitdiff