[re-adding ceph-devel] On Sat, 7 Sep 2013, Nigel Williams wrote: > On Sat, Sep 7, 2013 at 1:27 AM, Sage Weil <sage@xxxxxxxxxxx> wrote: > > It sounds like the problem is cluster B's pools have too few PGs, making > > the data distribution get all out of whack. > > Agree, it was too few PGs, I have no re-adjusted and it is busy > backfilling and evening out the data-distribution across the OSDs. > > My overall point is that the out-of-the-box defaults don't provide a > stable test-deployment (whereas older versions like 0.61 did), and so > minimally perhaps ceph-deploy needs to have a stab at choosing a > workable value of PGs? or alternatively the health warning could > include a note about PGs being too low. I agree; this is a general problem that we need to come up with a better solution to. One idea: - make ceph health warn when the pg distribution looks "bad" - too few pgs relative the # of osds - too many objects in a pool relative to the # of pgs and the above (We'll need to be a little creative to make thresholds that make sense.) If we have an interactive ceph-deploy new, we can also estimate how big the cluster will get and make a more sensible starting count. I like that less, though, as it potentially confusing and has more room for user error. sage > > > ceph osd dump | grep ^pool > > say, and how many OSDs do you have? > > I assume you mean PGs, it was the default (192?) and changing it to > 400 seems to have helped. There are 12 OSDs (4 per server, 3 servers). > > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
