From 8aa159befa58cd9059ad99c752146f3a5dbfcb8b Mon Sep 17 00:00:00 2001 From: Robert LeBlanc Date: Sun, 28 Feb 2016 09:34:31 -0700 Subject: [PATCH] doc: osd-config Add Configuration Options for op queue. Signed-off-by: Robert LeBlanc --- doc/rados/configuration/osd-config-ref.rst | 36 ++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/doc/rados/configuration/osd-config-ref.rst b/doc/rados/configuration/osd-config-ref.rst index 5e6f61ffe8982..68b140f6aac99 100644 --- a/doc/rados/configuration/osd-config-ref.rst +++ b/doc/rados/configuration/osd-config-ref.rst @@ -331,6 +331,42 @@ recovery operations to ensure optimal performance during recovery. :Default: ``2`` +``osd op queue`` + +:Description: This sets the type of queue to be used for prioritizing ops + in the OSDs. Both queues feature a strict sub-queue which is + dequeued before the normal queue. The normal queue is different + between implementations. The original PrioritizedQueue (``prio``) uses a + token bucket system which when there are sufficient tokens will + dequeue high priority queues first. If there are not enough + tokens available, queues are dequeued low priority to high priority. + The new WeightedPriorityQueue (``wpq``) dequeues all priorities in + relation to their priorities to prevent starvation of any queue. + WPQ should help in cases where a few OSDs are more overloaded + than others. Requires a restart. + +:Type: String +:Valid Choices: prio, wpq +:Default: ``prio`` + + +``osd op queue cut off`` + +:Description: This selects which priority ops will be sent to the strict + queue verses the normal queue. The ``low`` setting sends all + replication ops and higher to the strict queue, while the ``high`` + option sends only replication acknowledgement ops and higher to + the strict queue. Setting this to ``high`` should help when a few + OSDs in the cluster are very busy especially when combined with + ``wpq`` in the ``osd op queue`` setting. OSDs that are very busy + handling replication traffic could starve primary client traffic + on these OSDs without these settings. Requires a restart. + +:Type: String +:Valid Choices: low, high +:Default: ``low`` + + ``osd client op priority`` :Description: The priority set for client operations. It is relative to -- 2.39.5