Hello list. Deep scrub totally kills cluster performance. First of all, it takes several minutes to complete: 2018-12-09 01:39:53.857994 7f2d32fde700 0 log_channel(cluster) log [DBG] : 4.75 deep-scrub starts 2018-12-09 01:46:30.703473 7f2d32fde700 0 log_channel(cluster) log [DBG] : 4.75 deep-scrub ok
Second, while it runs, it consumes 100% of OSD time[1]. This is on an ordinary 7200RPM spinner. While this happens, VMs cannot access their disks, and that leads to service interruptions. I disabled scrub and deep-scrub operations for now, and have 2 major questions: - can I disable 'health warning' status for noscrub and nodeep-scrub? I thought there was a way to do this, but can't find it. I want my cluster to think it's healthy, so if any new 'slow requests' or anything else pops - it will change status to 'health warning' again; - is there a way to limit deepscrub impact on disk performance, or do I just have to go and buy SSDs? [1] https://imgur.com/a/TKH3uda
_______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
