Hello, On Thu, 20 Aug 2015 08:25:16 +0200 Jacek Jarosiewicz wrote:
> On 08/20/2015 03:07 AM, Christian Balzer wrote: > > For a realistic comparison with your current setup, a total rebuild > > would be in order. Provided your cluster is testing only at this point. > > > > Given your current HW, that means the same 2-3 HDDs per storage node > > and 1 SSD as journal. > > > > What exact maker/model are your SSDs? > > > > Again, more HDDs means more (sustainable) IOPS, so unless your space > > requirements (data and physical) are very demanding, double the amount > > of 3TB HDDs would be noticeably better. > > > > Christian > > > > The cluster is a test setup, eventually we will have lots more hdds > (probably we will fill both chassises with drives - 44 drives each), > just starting with this number for testing purposes. > > For the ssd's we use Intel DC S3710 (we ran into dsync problems with > intel 530 series drives before, so we switched to recommended ones). > Ah yes. The S3710s are 200GB, I guess the 240GB came from the 530s. ^o^ Also for use as journals the older 3700 is actually better suited, as it has a higher sequential write rate. In everything else the 3710 is faster. > By "total rebuild" do You mean reinitializing the whole cluster > (monitors/osds) and starting from scratch? > Well, not the the monitors, but starting from scratch might actually be the fastest way. Unless you have another 10 HDDs and 4 SSDs (1 per storage node) for journals lying around, to get a "fair" comparison to your current install. Realistically you would of course compare something that is about the same size and cost, so more like 16 HDDs. Christian -- Christian Balzer Network/Systems Engineer ch...@gol.com Global OnLine Japan/Fusion Communications http://www.gol.com/ _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
