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+======================
+ MDS Config Reference
+======================
+
+``mds_cache_memory_limit``
+
+:Description: The memory limit the MDS should enforce for its cache.
+:Type:  64-bit Integer Unsigned
+:Default: ``4G``
+
+``mds_cache_reservation``
+
+:Description: The cache reservation (memory or inodes) for the MDS cache to maintain.
+              Once the MDS begins dipping into its reservation, it will recall
+              client state until its cache size shrinks to restore the
+              reservation.
+:Type:  Float
+:Default: ``0.05``
+
+
+``mds_cache_mid``
+
+:Description: The insertion point for new items in the cache LRU 
+              (from the top).
+
+:Type:  Float
+:Default: ``0.7``
+
+
+``mds_dir_commit_ratio``
+
+:Description: The fraction of directory that is dirty before Ceph commits using 
+              a full update (instead of partial update).
+
+:Type:  Float
+:Default: ``0.5``
+
+
+``mds_dir_max_commit_size``
+
+:Description: The maximum size of a directory update before Ceph breaks it into 
+              smaller transactions (MB).
+              
+:Type:  32-bit Integer
+:Default: ``10``
+
+``mds_dir_max_entries``
+
+:Description: The maximum number of entries before any new entries are rejected
+              with ENOSPC.
+:Type:  64-bit Integer Unsigned
+:Default: ``0``
+
+``mds_decay_halflife``
+
+:Description: The half-life of MDS cache temperature.
+:Type:  Float
+:Default: ``5``
+
+``mds_beacon_interval``
+
+:Description: The frequency (in seconds) of beacon messages sent 
+              to the monitor.
+
+:Type:  Float
+:Default: ``4``
+
+
+``mds_beacon_grace``
+
+:Description: The interval without beacons before Ceph declares an MDS laggy 
+              (and possibly replace it).
+              
+:Type:  Float
+:Default: ``15``
+
+
+``mds_blocklist_interval``
+
+:Description: The blocklist duration for failed MDSs in the OSD map. Note,
+              this controls how long failed MDS daemons will stay in the
+              OSDMap blocklist. It has no effect on how long something is
+              blocklisted when the administrator blocklists it manually. For
+              example, ``ceph osd blocklist add`` will still use the default
+              blocklist time.
+:Type:  Float
+:Default: ``24.0*60.0``
+
+
+``mds_reconnect_timeout``
+
+:Description: The interval (in seconds) to wait for clients to reconnect 
+              during MDS restart.
+
+:Type:  Float
+:Default: ``45``
+
+
+``mds_tick_interval``
+
+:Description: How frequently the MDS performs internal periodic tasks.
+:Type:  Float
+:Default: ``5``
+
+
+``mds_dirstat_min_interval``
+
+:Description: The minimum interval (in seconds) to try to avoid propagating 
+              recursive stats up the tree.
+              
+:Type:  Float
+:Default: ``1``
+
+``mds_scatter_nudge_interval``
+
+:Description: How quickly dirstat changes propagate up.
+:Type:  Float
+:Default: ``5``
+
+
+``mds_client_prealloc_inos``
+
+:Description: The number of inode numbers to preallocate per client session.
+:Type:  32-bit Integer
+:Default: ``1000``
+
+
+``mds_early_reply``
+
+:Description: Determines whether the MDS should allow clients to see request 
+              results before they commit to the journal.
+
+:Type:  Boolean
+:Default: ``true``
+
+
+``mds_default_dir_hash``
+
+:Description: The function to use for hashing files across directory fragments.
+:Type:  32-bit Integer
+:Default: ``2`` (i.e., rjenkins)
+
+
+``mds_log_skip_corrupt_events``
+
+:Description: Determines whether the MDS should try to skip corrupt journal 
+              events during journal replay.
+              
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_log_max_events``
+
+:Description: The maximum events in the journal before we initiate trimming.
+              Set to ``-1`` to disable limits.
+              
+:Type:  32-bit Integer
+:Default: ``-1``
+
+
+``mds_log_max_segments``
+
+:Description: The maximum number of segments (objects) in the journal before 
+              we initiate trimming. Set to ``-1`` to disable limits.
+
+:Type:  32-bit Integer
+:Default: ``128``
+
+
+``mds_bal_sample_interval``
+
+:Description: Determines how frequently to sample directory temperature 
+              (for fragmentation decisions).
+              
+:Type:  Float
+:Default: ``3``
+
+
+``mds_bal_replicate_threshold``
+
+:Description: The maximum temperature before Ceph attempts to replicate 
+              metadata to other nodes.
+              
+:Type:  Float
+:Default: ``8000``
+
+
+``mds_bal_unreplicate_threshold``
+
+:Description: The minimum temperature before Ceph stops replicating 
+              metadata to other nodes.
+              
+:Type:  Float
+:Default: ``0``
+
+
+``mds_bal_split_size``
+
+:Description: The maximum directory size before the MDS will split a directory 
+              fragment into smaller bits.
+              
+:Type:  32-bit Integer
+:Default: ``10000``
+
+
+``mds_bal_split_rd``
+
+:Description: The maximum directory read temperature before Ceph splits 
+              a directory fragment.
+              
+:Type:  Float
+:Default: ``25000``
+
+
+``mds_bal_split_wr``
+
+:Description: The maximum directory write temperature before Ceph splits 
+              a directory fragment.
+              
+:Type:  Float
+:Default: ``10000``
+
+
+``mds_bal_split_bits``
+
+:Description: The number of bits by which to split a directory fragment.
+:Type:  32-bit Integer
+:Default: ``3``
+
+
+``mds_bal_merge_size``
+
+:Description: The minimum directory size before Ceph tries to merge 
+              adjacent directory fragments.
+              
+:Type:  32-bit Integer
+:Default: ``50``
+
+
+``mds_bal_interval``
+
+:Description: The frequency (in seconds) of workload exchanges between MDSs.
+:Type:  32-bit Integer
+:Default: ``10``
+
+
+``mds_bal_fragment_interval``
+
+:Description: The delay (in seconds) between a fragment being eligible for split
+              or merge and executing the fragmentation change.
+:Type:  32-bit Integer
+:Default: ``5``
+
+
+``mds_bal_fragment_fast_factor``
+
+:Description: The ratio by which frags may exceed the split size before
+              a split is executed immediately (skipping the fragment interval)
+:Type:  Float
+:Default: ``1.5``
+
+``mds_bal_fragment_size_max``
+
+:Description: The maximum size of a fragment before any new entries
+              are rejected with ENOSPC.
+:Type:  32-bit Integer
+:Default: ``100000``
+
+``mds_bal_idle_threshold``
+
+:Description: The minimum temperature before Ceph migrates a subtree 
+              back to its parent.
+              
+:Type:  Float
+:Default: ``0``
+
+
+``mds_bal_max``
+
+:Description: The number of iterations to run balancer before Ceph stops. 
+              (used for testing purposes only)
+
+:Type:  32-bit Integer
+:Default: ``-1``
+
+
+``mds_bal_max_until``
+
+:Description: The number of seconds to run balancer before Ceph stops. 
+              (used for testing purposes only)
+
+:Type:  32-bit Integer
+:Default: ``-1``
+
+
+``mds_bal_mode``
+
+:Description: The method for calculating MDS load. 
+
+              - ``0`` = Hybrid.
+              - ``1`` = Request rate and latency. 
+              - ``2`` = CPU load.
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_bal_min_rebalance``
+
+:Description: The minimum subtree temperature before Ceph migrates.
+:Type:  Float
+:Default: ``0.1``
+
+
+``mds_bal_min_start``
+
+:Description: The minimum subtree temperature before Ceph searches a subtree.
+:Type:  Float
+:Default: ``0.2``
+
+
+``mds_bal_need_min``
+
+:Description: The minimum fraction of target subtree size to accept.
+:Type:  Float
+:Default: ``0.8``
+
+
+``mds_bal_need_max``
+
+:Description: The maximum fraction of target subtree size to accept.
+:Type:  Float
+:Default: ``1.2``
+
+
+``mds_bal_midchunk``
+
+:Description: Ceph will migrate any subtree that is larger than this fraction 
+              of the target subtree size.
+              
+:Type:  Float
+:Default: ``0.3``
+
+
+``mds_bal_minchunk``
+
+:Description: Ceph will ignore any subtree that is smaller than this fraction 
+              of the target subtree size.
+              
+:Type:  Float
+:Default: ``0.001``
+
+
+``mds_bal_target_removal_min``
+
+:Description: The minimum number of balancer iterations before Ceph removes
+              an old MDS target from the MDS map.
+              
+:Type:  32-bit Integer
+:Default: ``5``
+
+
+``mds_bal_target_removal_max``
+
+:Description: The maximum number of balancer iterations before Ceph removes 
+              an old MDS target from the MDS map.
+              
+:Type:  32-bit Integer
+:Default: ``10``
+
+
+``mds_replay_interval``
+
+:Description: The journal poll interval when in standby-replay mode.
+              ("hot standby")
+              
+:Type:  Float
+:Default: ``1``
+
+
+``mds_shutdown_check``
+
+:Description: The interval for polling the cache during MDS shutdown.
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_thrash_exports``
+
+:Description: Ceph will randomly export subtrees between nodes (testing only).
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_thrash_fragments``
+
+:Description: Ceph will randomly fragment or merge directories.
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_dump_cache_on_map``
+
+:Description: Ceph will dump the MDS cache contents to a file on each MDSMap.
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_dump_cache_after_rejoin``
+
+:Description: Ceph will dump MDS cache contents to a file after 
+              rejoining the cache (during recovery).
+              
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_verify_scatter``
+
+:Description: Ceph will assert that various scatter/gather invariants 
+              are ``true`` (developers only).
+              
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_debug_scatterstat``
+
+:Description: Ceph will assert that various recursive stat invariants 
+              are ``true`` (for developers only).
+              
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_debug_frag``
+
+:Description: Ceph will verify directory fragmentation invariants 
+              when convenient (developers only).
+              
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_debug_auth_pins``
+
+:Description: The debug auth pin invariants (for developers only).
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_debug_subtrees``
+
+:Description: The debug subtree invariants (for developers only).
+:Type:  Boolean
+:Default:  ``false``
+
+
+``mds_kill_mdstable_at``
+
+:Description: Ceph will inject MDS failure in MDSTable code 
+              (for developers only).
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_kill_export_at``
+
+:Description: Ceph will inject MDS failure in the subtree export code 
+              (for developers only).
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_kill_import_at``
+
+:Description: Ceph will inject MDS failure in the subtree import code 
+              (for developers only).
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_kill_link_at``
+
+:Description: Ceph will inject MDS failure in hard link code 
+              (for developers only).
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_kill_rename_at``
+
+:Description: Ceph will inject MDS failure in the rename code 
+              (for developers only).
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_wipe_sessions``
+
+:Description: Ceph will delete all client sessions on startup 
+              (for testing only).
+              
+:Type:  Boolean
+:Default: ``false``
+
+
+``mds_wipe_ino_prealloc``
+
+:Description: Ceph will delete ino preallocation metadata on startup 
+              (for testing only).
+              
+:Type:  Boolean
+:Default: ``false``
+
+
+``mds_skip_ino``
+
+:Description: The number of inode numbers to skip on startup 
+              (for testing only).
+              
+:Type:  32-bit Integer
+:Default: ``0``
+
+
+``mds_min_caps_per_client``
+
+:Description: Set the minimum number of capabilities a client may hold.
+:Type: Integer
+:Default: ``100``
+
+
+``mds_max_ratio_caps_per_client``
+
+:Description: Set the maximum ratio of current caps that may be recalled during MDS cache pressure.
+:Type: Float
+:Default: ``0.8``