On Tue, 6 May 2014 18:57:04 +0300 Sergey Malinin wrote: > My vision of a well built node is when number of journal disks is equal > to number of data disks. You definitely don't want to lose 3 journals at > once in case of single drive failure. > While that certainly is true not everybody is having unlimited budgets. I'd expect the DC3700 to outlast the spinning rust, especially if the implementor is SMART enough to be replace things before something unforetold were to happen. However using a 100GB DC3700 with those drives isn't particular wise performance wise. I'd at least use the 200GB ones. Regards, Christian > > 06 ??? 2014 ?., ? 18:07, Xabier Elkano <xelkano at hostinet.com> > > ???????(?): > > > > > > Hi, > > > > I'm designing a new ceph pool with new hardware and I would like to > > receive some suggestion. > > I want to use a replica count of 3 in the pool and the idea is to buy 3 > > new servers with a 10-drive 2,5" chassis each and 2 10Gbps nics. I have > > in mind two configurations: > > > > 1- With journal in SSDs > > > > OS: 2xSSD intel SC3500 100G Raid 1 > > Journal: 2xSSD intel SC3700 100G, 3 journal for each SSD > > OSD: 6 SAS10K 900G (SAS2 6Gbps), each running an OSD process. Total > > size for OSDs: 5,4TB > > > > 2- With journal in a partition in the spinners. > > > > OS: 2xSSD intel SC3500 100G Raid 1 > > OSD+journal: 8 SAS15K 600G (SAS3 12Gbps), each runing an OSD process > > and its journal. Total size for OSDs: 3,6TB > > > > The budget in both configuration is similar, but the total capacity > > not. What would be the best configuration from the point of view of > > performance? In the second configuration I know the controller write > > back cache could be very critical, the servers has a LSI 3108 > > controller with 2GB Cache. I have to plan this storage as a KVM image > > backend and the goal is the performance over the capacity. > > > > On the other hand, with these new hardware, what would be the best > > choice: create a new pool in an existing cluster or create a complete > > new cluster? Are there any advantages in creating and maintaining an > > isolated new cluster? > > > > thanks in advance, > > Xabier > > > > > > _______________________________________________ > > ceph-users mailing list > > ceph-users at lists.ceph.com > > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com -- Christian Balzer Network/Systems Engineer chibi at gol.com Global OnLine Japan/Fusion Communications http://www.gol.com/
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