diff --git a/doc/rbd/rbd-replay.rst b/doc/rbd/rbd-replay.rst index cc21ac9eb69..e1c96b21720 100644 --- a/doc/rbd/rbd-replay.rst +++ b/doc/rbd/rbd-replay.rst @@ -4,13 +4,15 @@ .. index:: Ceph Block Device; RBD Replay -RBD Replay is a set of tools for capturing and replaying Rados Block Device (RBD) workloads. -To capture an RBD workload, ``lttng-tools`` must be installed on the client, and ``librbd`` on the clent must be the Giant release or later. -To replay an RBD workload, ``librbd`` on the clent must be the Giant release or later. +RBD Replay is a set of tools for capturing and replaying Rados Block Device +(RBD) workloads. To capture an RBD workload, ``lttng-tools`` must be installed +on the client, and ``librbd`` on the client must be the v0.87 (Giant) release +or later. To replay an RBD workload, ``librbd`` on the client must be the Giant +release or later. -Capture and replay takes three steps\: +Capture and replay takes three steps: -1) Capture the trace. Make sure to capture ``pthread_id`` context:: +#. Capture the trace. Make sure to capture ``pthread_id`` context:: mkdir -p traces lttng create -o traces librbd @@ -20,18 +22,21 @@ Capture and replay takes three steps\: # run RBD workload here lttng stop -2) Process the trace with `rbd-replay-prep`_:: +#. Process the trace with `rbd-replay-prep`_:: rbd-replay-prep traces/ust/uid/*/* replay.bin -3) Replay the trace with `rbd-replay`_. Use read-only until you know it's doing what you want:: +#. Replay the trace with `rbd-replay`_. Use read-only until you know + it's doing what you want:: rbd-replay --read-only replay.bin -.. important:: ``rbd-replay`` will destroy data by default. Do not use against an image you wish to keep, unless you use the ``--read-only`` option. +.. important:: ``rbd-replay`` will destroy data by default. Do not use against + an image you wish to keep, unless you use the ``--read-only`` option. -The replayed workload does not have to be against the same RBD image or even the same cluster as the captured workload. -To account for differences, you may need to use the ``--pool`` and ``--map-image`` options of ``rbd-replay``. +The replayed workload does not have to be against the same RBD image or even the +same cluster as the captured workload. To account for differences, you may need +to use the ``--pool`` and ``--map-image`` options of ``rbd-replay``. .. _rbd-replay: ../../man/8/rbd-replay .. _rbd-replay-prep: ../../man/8/rbd-replay-prep