ceph mons looks fine during the recovery. Using HDD with SSD journals. with recommeded CPU and RAM numbers. On Fri, Feb 22, 2019 at 4:40 PM David Turner <drakonstein@xxxxxxxxx> wrote: > > What about the system stats on your mons during recovery? If they are having a hard time keeping up with requests during a recovery, I could see that impacting client io. What disks are they running on? CPU? Etc. > > On Fri, Feb 22, 2019, 6:01 AM M Ranga Swami Reddy <swamireddy@xxxxxxxxx> wrote: >> >> Debug setting defaults are using..like 1/5 and 0/5 for almost.. >> Shall I try with 0 for all debug settings? >> >> On Wed, Feb 20, 2019 at 9:17 PM Darius Kasparavičius <daznis@xxxxxxxxx> wrote: >> > >> > Hello, >> > >> > >> > Check your CPU usage when you are doing those kind of operations. We >> > had a similar issue where our CPU monitoring was reporting fine < 40% >> > usage, but our load on the nodes was high mid 60-80. If it's possible >> > try disabling ht and see the actual cpu usage. >> > If you are hitting CPU limits you can try disabling crc on messages. >> > ms_nocrc >> > ms_crc_data >> > ms_crc_header >> > >> > And setting all your debug messages to 0. >> > If you haven't done you can also lower your recovery settings a little. >> > osd recovery max active >> > osd max backfills >> > >> > You can also lower your file store threads. >> > filestore op threads >> > >> > >> > If you can also switch to bluestore from filestore. This will also >> > lower your CPU usage. I'm not sure that this is bluestore that does >> > it, but I'm seeing lower cpu usage when moving to bluestore + rocksdb >> > compared to filestore + leveldb . >> > >> > >> > On Wed, Feb 20, 2019 at 4:27 PM M Ranga Swami Reddy >> > <swamireddy@xxxxxxxxx> wrote: >> > > >> > > Thats expected from Ceph by design. But in our case, we are using all >> > > recommendation like rack failure domain, replication n/w,etc, still >> > > face client IO performance issues during one OSD down.. >> > > >> > > On Tue, Feb 19, 2019 at 10:56 PM David Turner <drakonstein@xxxxxxxxx> wrote: >> > > > >> > > > With a RACK failure domain, you should be able to have an entire rack powered down without noticing any major impact on the clients. I regularly take down OSDs and nodes for maintenance and upgrades without seeing any problems with client IO. >> > > > >> > > > On Tue, Feb 12, 2019 at 5:01 AM M Ranga Swami Reddy <swamireddy@xxxxxxxxx> wrote: >> > > >> >> > > >> Hello - I have a couple of questions on ceph cluster stability, even >> > > >> we follow all recommendations as below: >> > > >> - Having separate replication n/w and data n/w >> > > >> - RACK is the failure domain >> > > >> - Using SSDs for journals (1:4ratio) >> > > >> >> > > >> Q1 - If one OSD down, cluster IO down drastically and customer Apps impacted. >> > > >> Q2 - what is stability ratio, like with above, is ceph cluster >> > > >> workable condition, if one osd down or one node down,etc. >> > > >> >> > > >> Thanks >> > > >> Swami >> > > >> _______________________________________________ >> > > >> 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 _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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