DOCS-15652 write to wire metric (#1963)

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

* DOCS-15652-write-to-wire-metric

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

Author: jason-price-mongodb

source/reference/command/serverStatus.txt

@@ -1507,7 +1507,8 @@ metrics
       network : {  // Added in MongoDB 6.2
          totalEgressConnectionEstablishmentTimeMillis : Long("<num>"),
          totalIngressTLSConnections : Long("<num>"),
-         totalIngressTLSHandshakeTimeMillis : Long("<num>")
+         totalIngressTLSHandshakeTimeMillis : Long("<num>"),
+         totalTimeForEgressConnectionAcquiredToWireMicros : Long("<num>")
       },
       operation : {
          numConnectionNetworkTimeouts : Long("<num>"),  // Added in MongoDB 6.2
@@ -5082,6 +5083,15 @@ transactions
    server have to wait for the TLS network handshake to complete. The
    number is cumulative and is the total after the server was started.
 
+.. serverstatus:: metrics.network.totalTimeForEgressConnectionAcquiredToWireMicros
+
+   .. versionadded:: 6.2
+
+   The total time in microseconds that operations wait between
+   acquisition of a server connection and writing the bytes to send to
+   the server over the network. The number is cumulative and is the
+   total after the server was started.
+
 .. serverstatus:: transactions.retriedCommandsCount
 
    |mongod-only|

source/reference/parameters.txt

@@ -1116,6 +1116,59 @@ General Parameters
 
       db.adminCommand( { setParameter: 1, slowConnectionThresholdMillis: 250 } )
 
+.. parameter:: connectionAcquisitionToWireLoggingRate
+
+   .. versionadded:: 6.2
+   
+   *Default*: 0.2
+
+   |both|
+
+   Value must be between 0 and 1 inclusive.
+
+   The value determines when an event is added to the :ref:`log
+   <log-messages-ref>` for connection acquisitions. The event contains
+   the:
+
+   - Message ``"Acquired connection for remote operation and completed
+     writing to wire"``.
+
+   - Time in microseconds that the operation waited between acquisition
+     of a server connection and writing the bytes to send to the server
+     over the network.
+
+   If the time from connection acquisition to writing the bytes is:
+
+   - Greater than or equal to the internal time limit (for example, 1000
+     microseconds), the event is always added to the log.
+
+   - Less than the internal time limit, the event is added to the log
+     based on the :parameter:`connectionAcquisitionToWireLoggingRate`
+     setting. For example, if
+     :parameter:`connectionAcquisitionToWireLoggingRate` is set to:
+
+     - ``0``, the event is never logged.
+
+     - ``0.4``, the event is logged 40% of the time.
+
+     - ``0.9``, the event is logged 90% of the time.
+
+     - ``1.0``, the event is always logged.
+
+   The following example sets
+   :parameter:`connectionAcquisitionToWireLoggingRate` to ``0.4``.
+
+   .. code-block:: bash
+
+      mongod --setParameter connectionAcquisitionToWireLoggingRate=0.4
+
+   Or, if using the :dbcommand:`setParameter` command within
+   :binary:`~bin.mongosh`:
+
+   .. code-block:: javascript
+
+      db.adminCommand( { setParameter: 1, connectionAcquisitionToWireLoggingRate: 0.4 } )
+
 .. parameter:: connPoolMaxConnsPerHost
 
    *Default*: 200

source/release-notes/6.2.txt

@@ -40,6 +40,7 @@ Starting in MongoDB 6.2, the :dbcommand:`serverStatus` command and the
      - :serverstatus:`metrics.network.totalEgressConnectionEstablishmentTimeMillis`
        :serverstatus:`metrics.network.totalIngressTLSConnections`
        :serverstatus:`metrics.network.totalIngressTLSHandshakeTimeMillis`
+       :serverstatus:`metrics.network.totalTimeForEgressConnectionAcquiredToWireMicros`
 
    * - Additions to :serverstatus:`metrics.operation` document.
      - :serverstatus:`metrics.operation.numConnectionNetworkTimeouts`
@@ -71,10 +72,12 @@ Collection Validation Improvements
 Server Parameters
 -----------------
 
-Starting in MongoDB 6.2, MongoDB adds the following new parameter:
+Starting in MongoDB 6.2, these server parameters were added:
 
 - :parameter:`slowConnectionThresholdMillis` sets the time limit to log
   the establishment of slow server connections. 
+- :parameter:`connectionAcquisitionToWireLoggingRate` determines when an
+  event is added to the log for connection acquisitions.
 
 Report an Issue
 ---------------