Nick, Tyler, many thanks for very helpful feedback! I spent many hours meditating on the following two links: http://www.supermicro.com/solutions/storage_ceph.cfm http://s3s.eu/cephshop
60- or even 72-disk nodes are very capacity-efficient, but will the 2 CPUs (even the fastest ones) be enough to handle Erasure Coding? Also as Nick stated with 4-5 nodes I cannot use high-M "K+M" combinations. I've did some calculations and found that the most efficient and safe configuration is to use 10 nodes with 29*6TB SATA and 7*200GB S3700 for journals. Assuming 6+3 EC profile that will give me 1.16 PB of effective space. Also I prefer not to use precious NVMe drives. Don't see any reason to use them. But what about RAM? Can I go with 64GB per node with above config? I've seen OSDs are consuming not more than 1GB RAM for replicated pools (even 6TB ones). But what is the typical memory usage of EC pools? Does anybody know that? Also, am I right that for 6+3 EC profile i need at least 10 nodes to feel comfortable (one extra node for redundancy)? And finally can someone recommend what EC plugin to use in my case? I know it's a difficult question but anyway? 2016-02-16 16:12 GMT+08:00 Nick Fisk <n...@fisk.me.uk>: > > >> -----Original Message----- >> From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of >> Tyler Bishop >> Sent: 16 February 2016 04:20 >> To: Василий Ангапов <anga...@gmail.com> >> Cc: ceph-users <ceph-users@lists.ceph.com> >> Subject: Re: [ceph-users] Recomendations for building 1PB RadosGW with >> Erasure Code >> >> You should look at a 60 bay 4U chassis like a Cisco UCS C3260. >> >> We run 4 systems at 56x6tB with dual E5-2660 v2 and 256gb ram. >> Performance is excellent. > > Only thing I will say to the OP, is that if you only need 1PB, then likely > 4-5 of these will give you enough capacity. Personally I would prefer to > spread the capacity around more nodes. If you are doing anything serious with > Ceph its normally a good idea to try and make each node no more than 10% of > total capacity. Also with Ec pools you will be limited to the K+M combo's you > can achieve with smaller number of nodes. > >> >> I would recommend a cache tier for sure if your data is busy for reads. >> >> Tyler Bishop >> Chief Technical Officer >> 513-299-7108 x10 >> >> >> >> tyler.bis...@beyondhosting.net >> >> >> If you are not the intended recipient of this transmission you are notified >> that disclosing, copying, distributing or taking any action in reliance on >> the >> contents of this information is strictly prohibited. >> >> ----- Original Message ----- >> From: "Василий Ангапов" <anga...@gmail.com> >> To: "ceph-users" <ceph-users@lists.ceph.com> >> Sent: Friday, February 12, 2016 7:44:07 AM >> Subject: [ceph-users] Recomendations for building 1PB RadosGW with >> Erasure Code >> >> Hello, >> >> We are planning to build 1PB Ceph cluster for RadosGW with Erasure Code. It >> will be used for storing online videos. >> We do not expect outstanding write performace, something like 200- >> 300MB/s of sequental write will be quite enough, but data safety is very >> important. >> What are the most popular hardware and software recomendations? >> 1) What EC profile is best to use? What values of K/M do you recommend? > > The higher total k+m you go, you will require more CPU and sequential > performance will degrade slightly as the IO's are smaller going to the disks. > However larger numbers allow you to be more creative with failure scenarios > and "replication" efficiency. > >> 2) Do I need to use Cache Tier for RadosGW or it is only needed for RBD? Is >> it > > Only needed for RBD, but depending on workload it may still benefit. If you > are mostly doing large IO's, the gains will be a lot smaller. > >> still an overall good practice to use Cache Tier for RadosGW? >> 3) What hardware is recommended for EC? I assume higher-clocked CPUs are >> needed? What about RAM? > > Total Ghz is more important (ie ghzxcores) Go with the cheapest/power > efficient you can get. Aim for somewhere around 1Ghz per disk. > >> 4) What SSDs for Ceph journals are the best? > > Intel S3700 or P3700 (if you can stretch) > > By all means explore other options, but you can't go wrong by buying these. > Think "You can't get fired for buying Cisco" quote!!! > >> >> Thanks a lot! >> >> Regards, Vasily. >> _______________________________________________ >> 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
