Hi Alexandre, Am 07.09.2017 um 19:31 schrieb Alexandre DERUMIER: > Hi Stefan > >>> Have you already done tests how he performance changes with bluestore >>> while putting all 3 block devices on the same ssd? > > > I'm going to test bluestore with 3 nodes , 18 x intel s3610 1,6TB in coming weeks. > > I'll send results on the mailing. Thanks! Greets, Stefan > ----- Mail original ----- > De: "Stefan Priebe, Profihost AG" <s.priebe@xxxxxxxxxxxx> > À: "Christian Balzer" <chibi@xxxxxxx>, "ceph-users" <ceph-users@xxxxxxxxxxxx> > Envoyé: Jeudi 7 Septembre 2017 08:03:31 > Objet: Re: PCIe journal benefit for SSD OSDs > > Hello, > Am 07.09.2017 um 03:53 schrieb Christian Balzer: >> >> Hello, >> >> On Wed, 6 Sep 2017 09:09:54 -0400 Alex Gorbachev wrote: >> >>> We are planning a Jewel filestore based cluster for a performance >>> sensitive healthcare client, and the conservative OSD choice is >>> Samsung SM863A. >>> >> >> While I totally see where you're coming from and me having stated that >> I'll give Luminous and Bluestore some time to mature, I'd also be looking >> into that if I were being in the planning phase now, with like 3 months >> before deployment. >> The inherent performance increase with Bluestore (and having something >> that hopefully won't need touching/upgrading for a while) shouldn't be >> ignored. > > Yes and that's the point where i'm currently as well. Thinking about how > to design a new cluster based on bluestore. > >> The SSDs are fine, I've been starting to use those recently (though not >> with Ceph yet) as Intel DC S36xx or 37xx are impossible to get. >> They're a bit slower in the write IOPS department, but good enough for me. > > I've never used the Intel DC ones but always the Samsung are the Intel > really faster? Have you disabled te FLUSH command for the Samsung ones? > They don't skip the command automatically like the Intel do. Sadly the > Samsung SM863 got more expensive over the last months. They were a lot > cheaper in the first month of 2016. May be the 2,5" optane intel ssds > will change the game. > >>> but was wondering if anyone has seen a positive >>> impact from also using PCIe journals (e.g. Intel P3700 or even the >>> older 910 series) in front of such SSDs? >>> >> NVMe journals (or WAL and DB space for Bluestore) are nice and can >> certainly help, especially if Ceph is tuned accordingly. >> Avoid non DC NVMes, I doubt you can still get 910s, they are officially >> EOL. >> You want to match capabilities and endurances, a DC P3700 800GB would be >> an OK match for 3-4 SM863a 960GB for example. > > That's a good point but makes the cluster more expensive. Currently > while using filestore i use one SSD for journal and data which works fine. > > With bluestore we've block, db and wal so we need 3 block devices per > OSD. If we need one PCIe or NVMe device per 3-4 devices it get's much > more expensive per host - currently running 10 OSDs / SSDs per Node. > > Have you already done tests how he performance changes with bluestore > while putting all 3 block devices on the same ssd? > > Greets, > Stefan > _______________________________________________ > 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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