ceph-mon disk with 500G with HDD (not journals/SSDs).  Yes, mon use
folder on FS on a disk

On Fri, Feb 22, 2019 at 5:13 PM David Turner <drakonst...@gmail.com> wrote:
>
> Mon disks don't have journals, they're just a folder on a filesystem on a 
> disk.
>
> On Fri, Feb 22, 2019, 6:40 AM M Ranga Swami Reddy <swamire...@gmail.com> 
> wrote:
>>
>> 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 <drakonst...@gmail.com> 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 <swamire...@gmail.com> 
>> > 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 <daz...@gmail.com> 
>> >> 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
>> >> > <swamire...@gmail.com> 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 <drakonst...@gmail.com> 
>> >> > > 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 
>> >> > > > <swamire...@gmail.com> 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@lists.ceph.com
>> >> > > >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
>> >> > > _______________________________________________
>> >> > > ceph-users mailing list
>> >> > > ceph-users@lists.ceph.com
>> >> > > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com

Reply via email to