Hi Daniel, And further to my theory about the spin lock or similar, increasing my > recovery by 4-16x using wpq sees my cpu rise to 10-15% ( from 3% )... > but using mclock, even at very very conservative recovery settings sees a > median CPU usage of some multiple of 100% (eg. a multiple of a machine > core/thread usage per osd). > > The issue has been narrowed down to waiting threads of a work queue shard being unblocked prematurely during the wait period prior to dequeuing a future work item from the mclock queue. This is leading to high CPU usage as you have observed. WPQ uses sleep to throttle various operations, but mclock based on the set QoS parameters could schedule operations in the future. The work queue threads should ideally relinquish CPU and block until the set time duration, but this is evidently not happening currently. While the fix is being worked upon, do continue to provide us your feedback and use wpq in the interim. Thanks! -Sridhar _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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