From: Sridhar Seshasayee Date: Thu, 4 Jun 2026 06:58:35 +0000 (+0530) Subject: doc/rados/configuration: Remove wpq recommendation warning for EC clusters X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=2cf1e713cec59c989602c001e710ba499005ab04;p=ceph.git doc/rados/configuration: Remove wpq recommendation warning for EC clusters Remove the warning that recommends using wpq scheduler as a fallback for EC clusters. This issue is addressed by considering EC recovery reads as background, assigning an accurate cost for those reads and tuning the QoS parameters associated with best-effort class of operations. Signed-off-by: Sridhar Seshasayee --- diff --git a/doc/rados/configuration/mclock-config-ref.rst b/doc/rados/configuration/mclock-config-ref.rst index 316e1faa5e1..fc5201b32fc 100644 --- a/doc/rados/configuration/mclock-config-ref.rst +++ b/doc/rados/configuration/mclock-config-ref.rst @@ -4,22 +4,6 @@ .. index:: mclock; configuration -.. warning:: On large clusters with erasure-coded pools, operators may - observe slow ops during recovery or backfill (for example, when an - OSD is drained out). Under mClock, EC sub-operation reads issued - during recovery are currently routed through the ``immediate`` - high-priority queue and bypass mClock throttling. When many OSDs - read concurrently from a single source OSD, this can saturate that - OSD's high-priority queue and starve client and background work. - As an interim measure, such deployments are advised to switch to - the ``WeightedPriorityQueue`` (``wpq``) scheduler. The change can - be applied cluster-wide and takes effect after each OSD is - restarted: - - .. prompt:: bash # - - ceph config set osd osd_op_queue wpq - QoS support in Ceph is implemented using a queuing scheduler based on `the dmClock algorithm`_. See :ref:`dmclock-qos` section for more details.