ceph/doc/create_cluster/mds_configuration_settings.rst

======================================
Metadata Server Configuration Settings
======================================

+-----------------------------------+-------------------------+------------+------------------------------------------------+
| Setting                           | Type                    | Default    | Description                                    |
+===================================+=========================+============+================================================+
| ``mds_max_file_size``             | 64-bit Integer Unsigned | 1ULL << 40 |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_cache_size``                | 32-bit Integer          | 100000     |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_cache_mid``                 | Float                   | .7         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_mem_max``                   | 32-bit Integer          | 1048576    | // KB                                          |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_dir_commit_ratio``          | Float                   | .5         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_dir_max_commit_size``       | 32-bit Integer          | 90         | // MB                                          |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_decay_halflife``            | Float                   | 5          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_beacon_interval``           | Float                   | 4          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_beacon_grace``              | Float                   | 15         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_blacklist_interval``        | Float                   | 24.0*60.0  | // how long to blacklist failed nodes          |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_session_timeout``           | Float                   | 60         | // cap bits and leases time out if client idle |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_session_autoclose``         | Float                   | 300        | // autoclose idle session                      |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_reconnect_timeout``         | Float                   | 45         | // secs to wait for clients during mds restart |   
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_tick_interval``             | Float                   | 5          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_dirstat_min_interval``      | Float                   | 1          | //try to avoid propagating more often than x   |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_scatter_nudge_interval``    | Float                   | 5          | // how quickly dirstat changes propagate up    |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_client_prealloc_inos``      | 32-bit Integer          | 1000       |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_early_reply``               | Boolean                 | true       |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_use_tmap``                  | Boolean                 | true       | // use trivialmap for dir updates              |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_default_dir_hash``          | 32-bit Integer          |            | CEPH_STR_HASH_RJENKINS                         |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_log``                       | Boolean                 | true       |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_log_skip_corrupt_events``   | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_log_max_events``            | 32-bit Integer          | -1         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_log_max_segments``          | 32-bit Integer          | 30         | // segment size defined by FileLayout  above   |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_log_max_expiring``          | 32-bit Integer          | 20         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_log_eopen_size``            | 32-bit Integer          | 100        | // # open inodes per log entry                 |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_sample_interval``       | Float                   | 3.0        | // every 5 seconds                             |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_replicate_threshold``   | Float                   | 8000       |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_unreplicate_threshold`` | Float                   | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_frag``                  | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_split_size``            | 32-bit Integer          | 10000      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_split_rd``              | Float                   | 25000      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_split_wr``              | Float                   | 10000      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_split_bits``            | 32-bit Integer          | 3          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_merge_size``            | 32-bit Integer          | 50         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_merge_rd``              | Float                   | 1000       |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_merge_wr``              | Float                   | 1000       |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_interval``              | 32-bit Integer          | 10         | // seconds                                     |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_fragment_interval``     | 32-bit Integer          | 5          | // seconds                                     |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_idle_threshold``        | Float                   | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_max``                   | 32-bit Integer          | -1         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_max_until``             | 32-bit Integer          | -1         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_mode``                  | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_min_rebalance``         | Float                   | .1         | // must be x above avg before we export        |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_min_start``             | Float                   | .2         | // if we need less x. we don't do anything     |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_need_min``              | Float                   | .8         | // take within this range of what we need      |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_need_max``              | Float                   | 1.2        |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_midchunk``              | Float                   | .3         | // any sub bigger than this taken in full      |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_minchunk``              | Float                   | .001       | // never take anything smaller than this       |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_target_removal_min``    | 32-bit Integer          | 5          | // min bal iters before old target is removed  |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_bal_target_removal_max``    | 32-bit Integer          | 10         | // max bal iters before old target is removed  |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_replay_interval``           | Float                   | 1.0        | // time to wait before starting replay again   |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_shutdown_check``            | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_thrash_exports``            | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_thrash_fragments``          | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_dump_cache_on_map``         | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_dump_cache_after_rejoin``   | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_verify_scatter``            | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_debug_scatterstat``         | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_debug_frag``                | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_debug_auth_pins``           | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_debug_subtrees``            | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_kill_mdstable_at``          | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_kill_export_at``            | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_kill_import_at``            | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_kill_link_at``              | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_kill_rename_at``            | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_wipe_sessions``             | Boolean                 | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_wipe_ino_prealloc``         | Boolean                 | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_skip_ino``                  | 32-bit Integer          | 0          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``max_mds``                       | 32-bit Integer          | 1          |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_standby_for_name``          | String                  | ""         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_standby_for_rank``          | 32-bit Integer          | -1         |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+
| ``mds_standby_replay``            | Boolean                 | false      |                                                |
+-----------------------------------+-------------------------+------------+------------------------------------------------+


//  make it (mds_session_timeout - mds_beacon_grace |