DOCS-15876-remove-chunkMigrationConcurrency (#2702)

Co-authored-by: jason-price-mongodb <[email protected]>

Author: 2 people

source/reference/command/serverStatus.txt

@@ -4222,7 +4222,6 @@ shardingStatistics
                "countDocsDeletedOnDonor" : NumberLong(<num>),
                "countDonorMoveChunkLockTimeout" : NumberLong(<num>),
                "unfinishedMigrationFromPreviousPrimary" : NumberLong(<num>),
-               "chunkMigrationConcurrency” : NumberLong(<num>),
                "catalogCache" : {
                   "numDatabaseEntries" : NumberLong(<num>),
                   "numCollectionEntries" : NumberLong(<num>),
@@ -4447,16 +4446,6 @@ shardingStatistics
 
    .. versionadded:: 4.4
 
-.. serverstatus:: shardingStatistics.chunkMigrationConcurrency
-
-   The number of threads on the source shard and the receiving shard for
-   performing :ref:`chunk migration <migrate-chunks-sharded-cluster>`
-   operations.
-
-   *Only present when run on a shard.*
-
-   *Available starting in MongoDB 6.0.5 (and 5.0.15).*
-
 .. serverstatus:: shardingStatistics.catalogCache
 
    A document with statistics about the cluster's routing information cache.

source/reference/parameters.txt

@@ -3014,49 +3014,6 @@ Sharding Parameters
 
       db.adminCommand( { setParameter: 1, chunkDefragmentationThrottlingMS: 10 } )
 
-.. parameter:: chunkMigrationConcurrency
-
-   *Available starting in MongoDB 6.0.5 (and 5.0.15).*
-
-   *Type*: integer
-
-   *Default*: 1
-
-   |both|
-
-   Specifies an integer that sets the number of threads on the source
-   shard and the receiving shard for :ref:`chunk migration
-   <migrate-chunks-sharded-cluster>`.
-   
-   Increasing the concurrency improves chunk migration performance, but
-   also increases the workload and disk IOPS usage on the the source
-   shard and the receiving shard.
-
-   Maximum value is 500.
-   
-   You should typically use half the total number of CPU cores as
-   threads. For example, if the total is 16 cores, set
-   ``chunkMigrationConcurrency`` to 8 threads (or fewer).
-
-   If ``chunkMigrationConcurrency`` is greater than ``1``, the
-   ``_secondaryThrottle`` configuration setting is ignored. The
-   ``_secondaryThrottle`` setting determines when the chunk migration
-   proceeds with the next document in the chunk. For details, see
-   :ref:`chunk-migration-replication`.
-
-   The following example sets ``chunkMigrationConcurrency`` to ``5``:
-
-   .. code-block:: bash
-
-      mongod --setParameter chunkMigrationConcurrency=5
-
-   During runtime, you can also set the parameter with the
-   :dbcommand:`setParameter` command:
-
-   .. code-block:: javascript
-
-      db.adminCommand( { setParameter: 1, chunkMigrationConcurrency: 5 } )
-
 .. parameter:: disableResumableRangeDeleter
 
    .. versionadded:: 4.4