doc: document osd tell bench

Signed-off-by: Florian Haas <florian@hastexo.com>

diff --git a/doc/control.rst b/doc/control.rst
index b43767a1301e06b59dbb381caa63dc944ff34b70..ec1c75dd65aa8684341d1cf0259fa6a636bdfe66 100644 (file)
--- a/doc/control.rst
+++ b/doc/control.rst
@@ -263,6 +263,14 @@ TODO: what does this actually do ::
 Sends a repair command to osdN. To send the command to all osds, use ``*``.
 TODO: what does this actually do
 
+::
+
+       $ ceph osd tell N bench [BYTES_PER_WRITE] [TOTAL_BYTES]
+
+Runs a simple throughput benchmark against osdN, writing ``TOTAL_BYTES``
+in write requests of ``BYTES_PER_WRITE`` each. By default, the test
+writes 1 GB in total in 4-MB increments.
+
 MDS subsystem
 -------------