cleanup of JavaScript lock in reference pages

source/applications/map-reduce.txt

@@ -227,12 +227,7 @@ The map-reduce operation is composed of many tasks, including:
 These various tasks take the following locks:
 
 - The read phase takes a read lock.  It yields every 100 documents.
-
-- The JavaScript code (i.e. ``map``, ``reduce``, ``finalize``
-  functions) is executed in a single thread, taking a JavaScript lock;
-  however, most JavaScript tasks in map-reduce are very short and
-  yield the lock frequently.
-
+
 - The insert into the temporary collection takes a write lock for a
   single write.
 
@@ -242,8 +237,11 @@ These various tasks take the following locks:
   If the output collection exists, then the output actions (i.e.
   ``merge``, ``replace``, ``reduce``) take a write lock.
 
-Although single-threaded, the map-reduce tasks interleave and appear to
-run in parallel.
+.. versionchanged:: 2.4
+   The V8 JavaScript engine added in 2.4 allows multiple JavaScript
+   operations to run at the same time. Prior to 2.4, JavaScript code
+   (i.e. ``map``, ``reduce``, ``finalize`` functions) executed in a
+   single thread, taking a JavaScript lock.
 
 .. note::
 

source/reference/command/eval.txt

@@ -141,10 +141,6 @@ eval
 
       - .. include:: /includes/fact-eval-lock.rst
 
-      - :dbcommand:`eval` also takes a JavaScript lock. 
-
-        .. modified in 2.4 version, the JavaScript lock is up to and including version 2.2
-
       - Do not use :dbcommand:`eval` for long running operations as
         :dbcommand:`eval` blocks all other operations. Consider using
         :doc:`other server side code execution options
@@ -158,4 +154,9 @@ eval
 
       - .. include:: /includes/fact-eval-authentication.rst
 
+   .. versionchanged:: 2.4
+      The V8 JavaScript engine added in 2.4 allows multiple JavaScript
+      operations to run at the same time. Prior to 2.4,
+      :dbcommand:`eval` would take a JavaScript lock.
+
    .. seealso:: :doc:`/applications/server-side-javascript`

source/reference/command/group.txt

@@ -68,14 +68,10 @@ group
 
    .. warning::
 
-      - The :dbcommand:`group` command does not work with
-        :term:`sharded clusters <sharded cluster>`. Use the
-        :term:`aggregation framework` or :term:`map-reduce` in
-        :term:`sharded environments <sharding>`.
-
-      - The :dbcommand:`group` command takes a read lock and does not
-        allow any other threads to execute JavaScript while it is
-        running.
+      The :dbcommand:`group` command does not work with :term:`sharded
+      clusters <sharded cluster>`. Use the :term:`aggregation
+      framework` or :term:`map-reduce` in :term:`sharded environments
+      <sharding>`.
 
    .. note::
 
@@ -92,6 +88,9 @@ group
 
       - .. include:: /includes/fact-group-map-reduce-where-limitations-in-24.rst
 
+      - Prior to 2.4, the :dbcommand:`group` command took a JavaScript
+        lock.
+
    For the shell, MongoDB provides a wrapper method
    :method:`db.collection.group()`; however, the
    :method:`db.collection.group()` method takes the ``keyf`` field and

source/reference/method/db.collection.group.txt

@@ -52,14 +52,10 @@ db.collection.group()
 
    .. warning::
 
-      - The :method:`db.collection.group()` method does not work with
-        :term:`sharded clusters <sharded cluster>`. Use the
-        :term:`aggregation framework` or :term:`map-reduce` in
-        :term:`sharded environments <sharding>`.
-
-      - The :dbcommand:`group` command takes a read lock and does not
-        allow any other threads to execute JavaScript while it is
-        running.
+      The :method:`db.collection.group()` method does not work with
+      :term:`sharded clusters <sharded cluster>`. Use the
+      :term:`aggregation framework` or :term:`map-reduce` in
+      :term:`sharded environments <sharding>`.
 
    .. note::
 
@@ -76,6 +72,9 @@ db.collection.group()
 
       - .. include:: /includes/fact-group-map-reduce-where-limitations-in-24.rst
 
+      - Prior to 2.4, the :method:`db.collection.group()` method took a
+        JavaScript lock.
+
 Consider the following examples of the :method:`db.collection.group()` method:
 
 The examples assume an ``orders`` collection with documents of the

source/reference/method/db.eval.txt

@@ -98,10 +98,6 @@ db.eval()
       .. |nolockobject| replace:: :dbcommand:`eval` *command*
 
       - .. include:: /includes/fact-eval-lock.rst
-
-      - :method:`db.eval()` also takes a JavaScript lock.
-
-        .. modified in 2.4 version, the JavaScript lock is up to and including version 2.2
 
       - Do not use :method:`db.eval()` for long running operations, as
         :method:`db.eval()` blocks all other operations. Consider using
@@ -116,6 +112,11 @@ db.eval()
 
       - .. include:: /includes/fact-eval-authentication.rst
 
+   .. versionchanged:: 2.4
+      The V8 JavaScript engine added in 2.4 allows multiple JavaScript
+      operations to run at the same time. Prior to 2.4,
+      :method:`db.eval()` would take a JavaScript lock.
+
    .. seealso::
 
       :doc:`/applications/server-side-javascript`