summaryrefslogtreecommitdiffstats
path: root/doc/mgr/localpool.rst
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--doc/mgr/localpool.rst37
1 files changed, 37 insertions, 0 deletions
diff --git a/doc/mgr/localpool.rst b/doc/mgr/localpool.rst
new file mode 100644
index 000000000..fe8bd3942
--- /dev/null
+++ b/doc/mgr/localpool.rst
@@ -0,0 +1,37 @@
+Local Pool Module
+=================
+
+The *localpool* module can automatically create RADOS pools that are
+localized to a subset of the overall cluster. For example, by default, it will
+create a pool for each distinct ``rack`` in the cluster. This can be useful for
+deployments where it is desirable to distribute some data locally and other data
+globally across the cluster. One use-case is measuring performance and testing
+behavior of specific drive, NIC, or chassis models in isolation.
+
+Enabling
+--------
+
+The *localpool* module is enabled with::
+
+ ceph mgr module enable localpool
+
+Configuring
+-----------
+
+The *localpool* module understands the following options:
+
+* **subtree** (default: `rack`): which CRUSH subtree type the module
+ should create a pool for.
+* **failure_domain** (default: `host`): what failure domain we should
+ separate data replicas across.
+* **pg_num** (default: `128`): number of PGs to create for each pool
+* **num_rep** (default: `3`): number of replicas for each pool.
+ (Currently, pools are always replicated.)
+* **min_size** (default: none): value to set min_size to (unchanged from Ceph's default if this option is not set)
+* **prefix** (default: `by-$subtreetype-`): prefix for the pool name.
+
+These options are set via the config-key interface. For example, to
+change the replication level to 2x with only 64 PGs, ::
+
+ ceph config set mgr mgr/localpool/num_rep 2
+ ceph config set mgr mgr/localpool/pg_num 64