Hi sage, Am 14.07.2013 um 17:01 schrieb Sage Weil <sage@xxxxxxxxxxx>: > On Sun, 14 Jul 2013, Stefan Priebe wrote: >> Hello list, >> >> might this be a problem due to having too much PGs? I've 370 per OSD instead >> of having 33 / OSD (OSDs*100/3). > > That might exacerbate it. > > Can you try setting > > osd min pg log entries = 50 > osd max pg log entries = 100 What does that exactly do? And why is a restart of all osds needed. Thanks! > across your cluster, restarting your osds, and see if that makes a > difference? I'm wondering if this is a problem with pg log rewrites after > peering. Note that adding that option and restarting isn't enough to > trigger the trim; you have to hit the cluster with some IO too, and (if > this is the source of your problem) the trim itself might be expensive. > So add it, restart, do a bunch of io (to all pools/pgs if you can), and > then see if the problem is still present? Will try can't produce a write to every pg. it's a prod. Cluster with KVM rbd. But it has 800-1200 iop/s per second. > > Also note that the lower osd min pg log entries means that the osd cannot > be down as long without requiring a backfill (50 ios per pg). These > probably aren't the values that we want, but I'd like to find out whether > the pg log rewrites after peering in cuttlefish are the culprit here. > > Thanks! > >> Is there any plan for PG merging? > > Not right now. :( I'll talk to Sam, though, to see how difficult it > would be given the split approach we settled on. > > Thanks! > sage > > >> >> Stefan >>> Hello list, >>> >>> anyone else here who always has problems bringing back an offline OSD? >>> Since cuttlefish i'm seeing slow requests for the first 2-5 minutes >>> after bringing an OSD oinline again but that's so long that the VMs >>> crash as they think their disk is offline... >>> >>> Under bobtail i never had any problems with that. >>> >>> Please HELP! >>> >>> Greets, >>> Stefan >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> >> _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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