(DOCS-15619): Add --listenBacklog parameter to mongos reference (#2030)

* (DOCS-15619): Add --listenBacklog parameter to mongos reference

* create include file

* convert to rst file

Author: davidhou17

source/includes/parameter-listenbacklog.rst

@@ -0,0 +1,42 @@
+.. option:: --listenBacklog <number>
+
+   *Default*: Target system ``SOMAXCONN`` constant
+   
+   The maximum number of connections that can exist in the listen
+   queue.
+   
+   .. warning ::
+   
+      Consult your local system's documentation to understand the
+      limitations and configuration requirements before using this
+      parameter.
+   
+   .. important::
+   
+      To prevent undefined behavior, specify a value for this
+      parameter between ``1`` and the local system ``SOMAXCONN``
+      constant.
+   
+   The default value for the ``listenBacklog`` parameter is set at
+   compile time to the target system ``SOMAXCONN`` constant.
+   ``SOMAXCONN`` is the maximum valid value that is documented for
+   the *backlog* parameter to the *listen* system call.
+   
+   Some systems may interpret ``SOMAXCONN`` symbolically, and others
+   numerically. The actual *listen backlog* applied in practice may
+   differ from any numeric interpretation of the ``SOMAXCONN`` constant
+   or argument to ``--listenBacklog``, and may also be constrained by
+   system settings like ``net.core.somaxconn`` on Linux.
+   
+   Passing a value for the ``listenBacklog`` parameter that exceeds the
+   ``SOMAXCONN`` constant for the local system is, by the letter of the
+   standards, undefined behavior. Higher values may be silently integer
+   truncated, may be ignored, may cause unexpected resource
+   consumption, or have other adverse consequences.
+   
+   On systems with workloads that exhibit connection spikes, for which
+   it is empirically known that the local system can honor higher
+   values for the *backlog* parameter than the ``SOMAXCONN`` constant,
+   setting the ``listenBacklog`` parameter to a higher value may reduce
+   operation latency as observed by the client by reducing the number
+   of connections which are forced into a backoff state.

source/reference/program/mongod.txt

@@ -353,49 +353,7 @@ Core Options
    - Set :option:`--bind_ip_all` to ``true``.
 
 
-.. option:: --listenBacklog <number>
-
-   *Default*: Target system ``SOMAXCONN`` constant
-   
-   The maximum number of connections that can exist in the listen
-   queue.
-   
-   .. warning ::
-   
-      Consult your local system's documentation to understand the
-      limitations and configuration requirements before using this
-      parameter.
-   
-   .. important::
-   
-      To prevent undefined behavior, specify a value for this
-      parameter between ``1`` and the local system ``SOMAXCONN``
-      constant.
-   
-   The default value for the ``listenBacklog`` parameter is set at
-   compile time to the target system ``SOMAXCONN`` constant.
-   ``SOMAXCONN`` is the maximum valid value that is documented for
-   the *backlog* parameter to the *listen* system call.
-   
-   Some systems may interpret ``SOMAXCONN`` symbolically, and others
-   numerically. The actual *listen backlog* applied in practice may
-   differ from any numeric interpretation of the ``SOMAXCONN`` constant
-   or argument to ``--listenBacklog``, and may also be constrained by
-   system settings like ``net.core.somaxconn`` on Linux.
-   
-   Passing a value for the ``listenBacklog`` parameter that exceeds the
-   ``SOMAXCONN`` constant for the local system is, by the letter of the
-   standards, undefined behavior. Higher values may be silently integer
-   truncated, may be ignored, may cause unexpected resource
-   consumption, or have other adverse consequences.
-   
-   On systems with workloads that exhibit connection spikes, for which
-   it is empirically known that the local system can honor higher
-   values for the *backlog* parameter than the ``SOMAXCONN`` constant,
-   setting the ``listenBacklog`` parameter to a higher value may reduce
-   operation latency as observed by the client by reducing the number
-   of connections which are forced into a backoff state.
-
+.. include:: /includes/parameter-listenbacklog.rst
 
 
 .. option:: --maxConns <number>

source/reference/program/mongos.txt

@@ -15,7 +15,7 @@
 .. contents:: On this page
    :local:
    :backlinks: none
-   :depth: 1
+   :depth: 2
    :class: singlecol
 
 Synopsis
@@ -258,6 +258,8 @@ Core Options
       is, you can specify one or the other, but not both.
 
 
+.. include:: /includes/parameter-listenbacklog.rst
+
 
 .. option:: --maxConns <number>