.. _upmap:
+=======================================
Using pg-upmap
-==============
+=======================================
In Luminous v12.2.z and later releases, there is a *pg-upmap* exception table
in the OSDMap that allows the cluster to explicitly map specific PGs to
However, there is an important caveat when it comes to this new feature: it
requires all clients to understand the new *pg-upmap* structure in the OSDMap.
+Online Optimization
+===================
+
Enabling
--------
ceph features
-Balancer module
+Balancer Module
---------------
The `balancer` module for ``ceph-mgr`` will automatically balance the number of
PGs per OSD. See :ref:`balancer`
-Offline optimization
---------------------
+Offline Optimization
+====================
-Upmap entries are updated with an offline optimizer that is built into
-``osdmaptool``.
+Upmap entries are updated with an offline optimizer that is built into the
+:ref:`osdmaptool`.
#. Grab the latest copy of your osdmap: