The changes you are looking for are coming from Sandisk in the ceph "Jewel" release coming up. Based on benchmarks and testing, sandisk has really contributed heavily on the tuning aspects and are promising 90%+ native iop of a drive in the cluster. The biggest changes will come from the memory allocation with writes. Latency is going to be a lot lower. ----- Original Message ----- From: "David" <david@xxxxxxxxxx> To: "Wido den Hollander" <wido@xxxxxxxx> Cc: ceph-users@xxxxxxxxxxxxxx Sent: Sunday, January 17, 2016 6:49:25 AM Subject: Re: Again - state of Ceph NVMe and SSDs Thanks Wido, those are good pointers indeed :) So we just have to make sure the backend storage (SSD/NVMe journals) won’t be saturated (or the controllers) and then go with as many RBD per VM as possible. Kind Regards, David Majchrzak 16 jan 2016 kl. 22:26 skrev Wido den Hollander <wido@xxxxxxxx>: > On 01/16/2016 07:06 PM, David wrote: >> Hi! >> >> We’re planning our third ceph cluster and been trying to find how to >> maximize IOPS on this one. >> >> Our needs: >> * Pool for MySQL, rbd (mounted as /var/lib/mysql or equivalent on KVM >> servers) >> * Pool for storage of many small files, rbd (probably dovecot maildir >> and dovecot index etc) >> > > Not completely NVMe related, but in this case, make sure you use > multiple disks. > > For MySQL for example: > > - Root disk for OS > - Disk for /var/lib/mysql (data) > - Disk for /var/log/mysql (binary log) > - Maybe even a InnoDB logfile disk > > With RBD you gain more performance by sending I/O into the cluster in > parallel. So when ever you can, do so! > > Regarding small files, it might be interesting to play with the stripe > count and stripe size there. By default this is 1 and 4MB. But maybe 16 > and 256k work better here. > > With Dovecot as well, use a different RBD disk for the indexes and a > different one for the Maildir itself. > > Ceph excels at parallel performance. That is what you want to aim for. > >> So I’ve been reading up on: >> >> https://communities.intel.com/community/itpeernetwork/blog/2015/11/20/the-future-ssd-is-here-pcienvme-boosts-ceph-performance >> >> and ceph-users from october 2015: >> >> http://www.spinics.net/lists/ceph-users/msg22494.html >> >> We’re planning something like 5 OSD servers, with: >> >> * 4x 1.2TB Intel S3510 >> * 8st 4TB HDD >> * 2x Intel P3700 Series HHHL PCIe 400GB (one for SSD Pool Journal and >> one for HDD pool journal) >> * 2x 80GB Intel S3510 raid1 for system >> * 256GB RAM >> * 2x 8 core CPU Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz or better >> >> This cluster will probably run Hammer LTS unless there are huge >> improvements in Infernalis when dealing 4k IOPS. >> >> The first link above hints at awesome performance. The second one from >> the list not so much yet.. >> >> Is anyone running Hammer or Infernalis with a setup like this? >> Is it a sane setup? >> Will we become CPU constrained or can we just throw more RAM on it? :D >> >> Kind Regards, >> David Majchrzak >> >> >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > > > -- > Wido den Hollander > 42on B.V. > Ceph trainer and consultant > > Phone: +31 (0)20 700 9902 > Skype: contact42on > _______________________________________________ > 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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