(DOCSP-34349) Adds release notes and compatibility changes for 7.2 (#5242)

* DOCS-16363 Document killedDueToMaxTimeMSExpired under serverStatus (#5193)

* DOCS-16363 Document killedDueToMaxTimeMSExpired under serverStatus

* add to TOC

* wording

* build error

* Includes PM external review changes

* Revert "Includes PM external review changes"

This reverts commit 0263ebe646848bf840c75b414815d3daa660e9fc.

* Includes changes from PM review

* Includes copy review changes

---------

Co-authored-by: Alison Huh <[email protected]>

Author: sarahsimpers

source/core/hashed-sharding.txt

@@ -138,6 +138,8 @@ If you shard a populated collection using a hashed shard key:
 - After the initial chunk creation, the balancer moves ranges of the
   initial chunk when it needs to balance data.
 
+.. _shard-empty-collection:
+
 Shard an Empty Collection
 ~~~~~~~~~~~~~~~~~~~~~~~~~
 

source/release-notes/7.2-compatibility.txt

@@ -40,3 +40,10 @@ Renamed Metrics
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. include:: /includes/fact-encryption-options-create-collection.rst
+   
+``routingTableCacheChunkBucketSize`` Must Be Greater Than ``0``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Starting in MongoDB 7.2, the
+:parameter:`routingTableCacheChunkBucketSize` parameter's value must be
+greater than ``0``. Previously, this value could equal to ``0``.

source/release-notes/7.2.txt

@@ -42,6 +42,22 @@ Starting in MongoDB 7.2, the :dbcommand:`serverStatus` command and the
 - :serverstatus:`metrics.operation.killedDueToMaxTimeMSExpired`
 - :serverstatus:`readPreferenceCounters`
 
+``getField`` Field Supports All Strings
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Starting in MongoDB 7.2, you can specify any valid :ref:`expression 
+<aggregation-expressions>` that resolves to a string for the ``field``
+input of the :expression:`$getField` operator. In earlier versions,
+``field`` accepts only string constants.
+
+Default Chunks Per Shard
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Starting in MongoDB 7.2, when you :ref:`shard an empty collection
+<shard-empty-collection>` with a hashed shard key, the operation
+creates one chunk per shard by default. Previously, the operation
+created two chunks by default.
+
 .. toctree::
    :titlesonly:
    :hidden: