DOCS-10686: serverStatus and logical sessions info

Author: kay-kim

source/reference/command/serverStatus.txt

@@ -563,6 +563,84 @@ globalLock
 
    The number of active client connections performing write operations.
 
+.. _server-status-logicalSessions:
+
+logicalSessionRecordCache
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. versionadded:: 3.6
+
+.. code-block:: javascript
+
+   "logicalSessionRecordCache" : {
+      "activeSessionsCount" : <num>,
+      "sessionsCollectionJobCount" : <num>,
+      "lastSessionsCollectionJobDurationMillis" : <num>,
+      "lastSessionsCollectionJobTimestamp" : <Date>,
+      "lastSessionsCollectionJobEntriesRefreshed" : <num>,
+      "lastSessionsCollectionJobEntriesEnded" : <num>,
+      "lastSessionsCollectionJobCursorsClosed" : <num>,
+      "transactionReaperJobCount" : <num>,
+      "lastTransactionReaperJobDurationMillis" : <num>,
+      "lastTransactionReaperJobTimestamp" : <Date>,
+      "lastTransactionReaperJobEntriesCleanedUp" : <num>
+   },
+
+.. serverstatus:: logicalSessionRecordCache.activeSessionsCount
+
+   The number of all active local sessions cached in memory by the
+   :program:`mongod` or :program:`mongos` instance since the last
+   refresh period.
+
+   .. seealso:: :pipeline:`$listLocalSessions`, :parameter:`logicalSessionRefreshMinutes`
+
+.. serverstatus:: logicalSessionRecordCache.sessionsCollectionJobCount
+
+   The number that tracks the number of times the refresh process has
+   run on the :data:`config.system.sessions` collection.
+
+   .. seealso:: :parameter:`logicalSessionRefreshMinutes`
+
+.. serverstatus:: logicalSessionRecordCache.lastSessionsCollectionJobDurationMillis
+
+   The length in milliseconds of the last refresh.
+
+.. serverstatus:: logicalSessionRecordCache.lastSessionsCollectionJobTimestamp
+
+   The time at which the last refresh occurred.
+
+.. serverstatus:: logicalSessionRecordCache.lastSessionsCollectionJobEntriesRefreshed
+
+   The number of sessions that were refreshed during the last refresh.
+
+.. serverstatus:: logicalSessionRecordCache.lastSessionsCollectionJobEntriesEnded"
+
+   The number of sessions that ended during the last refresh.
+ 
+.. serverstatus:: logicalSessionRecordCache.lastSessionsCollectionJobCursorsClosed"
+
+   The number of cursors that were closed during the last
+   :data:`config.system.sessions` collection refresh.
+
+.. serverstatus:: logicalSessionRecordCache.transactionReaperJobCount"
+
+   The number that tracks the number of times the transaction record
+   cleanup process has run on the :data:`config.transactions`
+   collection.
+
+.. serverstatus:: logicalSessionRecordCache.lastTransactionReaperJobDurationMillis"
+
+   The length (in milleseconds) of the last transaction record cleanup.
+
+.. serverstatus:: logicalSessionRecordCache.lastTransactionReaperJobTimestamp"
+
+   The time of the last transaction record cleanup.
+
+.. serverstatus:: logicalSessionRecordCache.lastTransactionReaperJobEntriesCleanedUp"
+
+   The number of entries in the :data:`config.transactions` collection
+   that were deleted during the last transaction record cleanup.
+
 .. _locks:
 .. _server-status-locks:
 

source/release-notes/3.6.txt

@@ -69,21 +69,23 @@ MongoDB 3.6 adds the following new aggregation pipeline stages:
    * - Operator
      - Description
 
+   * - :pipeline:`$currentOp`
+
+     - Returns a stream of documents containing information
+       on active and/or dormant operations on a :program:`mongod`
+       instance. Uses the new aggregation helper
+       :method:`db.aggregate()`.
+
    * - :pipeline:`$listSessions`
 
      - Lists sessions in the ``system.sessions`` collection in the
-       ``config`` database.
+       ``config`` database. Uses the new aggregation helper
+       :method:`db.aggregate()`.
 
    * - :pipeline:`$listLocalSessions`
 
      - Lists sessions cached in memory by the server.
 
-   * - :pipeline:`$currentOp`
-
-     - Returns a stream of documents containing information
-       on active and/or dormant operations on a :program:`mongod`
-       instance.
-
 New Aggregation Operators
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -127,6 +129,8 @@ aggregations that do not rely on an underlying collection, such
 as those that start with :pipeline:`$currentOp` or
 :pipeline:`$listLocalSessions`.
 
+See also :ref:`3.6-agg-stages` added to support sessions.
+
 New Aggregation Variable
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -336,7 +340,14 @@ pipeline stages:
 
    * - :pipeline:`$listLocalSessions`
 
-     - Lists sessions cached in memory by the server.
+     - Lists sessions cached in memory by the server. Uses the new
+       aggregation helper :method:`db.aggregate()`.
+
+General
+~~~~~~~
+
+:dbcommand:`serverStatus` returns information on the number of
+:ref:`server-status-logicalSessions`.
 
 Command Options
 ~~~~~~~~~~~~~~~
@@ -394,6 +405,7 @@ The following new parameters are available for server sessions:
 
 - :parameter:`maxAcceptableLogicalClockDriftSecs`
 
+
 JSON Schema
 -----------