Increasing pg_num will lead to several slow requests and cluster freeze, but due to creating pgs operation , for what I’ve seen until now. During the creation period all the request are frozen , and the creation period take a lot of time even for 128 pgs. I’ve observed that during creation period most of the OSD goes at 100% of their performance capacity. I think that without operation running in the cluster I’ll be able to upgrade pg_num quickly without causing down time several times. Matteo > Il giorno 02 gen 2017, alle ore 15:02, ceph@xxxxxxxxxxxxxx ha scritto: > > Well, as the doc said: >> Set or clear the pause flags in the OSD map. If set, no IO requests will be sent to any OSD. Clearing the flags via unpause results in resending pending requests. > If you do that on a production cluster, that means your cluster will no > longer be in production :) > > Depending on your needs, but .. > Maybe you want do this operation as fast as possible > Or maybe you want to make that operation as transparent as possible, > from a user point of view > > You may have a look at osd_recovery_op_priority & > osd_client_op_priority, they might be interesting for you > > On 02/01/2017 14:37, Matteo Dacrema wrote: >> Hi All, >> >> what happen if I set pause flag on a production cluster? >> I mean, will all the request remain pending/waiting or all the volumes attached to the VMs will become read-only? >> >> I need to quickly upgrade placement group number from 3072 to 8192 or better to 165336 and I think doing it without client operations will be much faster. >> >> Thanks >> Regards >> Matteo >> >> >> >> >> _______________________________________________ >> 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 > > -- > Questo messaggio e' stato analizzato con Libra ESVA ed e' risultato non infetto. > Seguire il link qui sotto per segnalarlo come spam: > http://mx01.enter.it/cgi-bin/learn-msg.cgi?id=9F3C956B85.A333A > > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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