On 09/29/2014 03:58 AM, Dan Van Der Ster wrote: > Hi Emmanuel, > This is interesting, because we?ve had sales guys telling us that those Samsung drives are definitely the best for a Ceph journal O_o ! Our sales guys or Samsung sales guys? :) If it was ours, let me know. > The conventional wisdom has been to use the Intel DC S3700 because of its massive durability. The S3700 is definitely one of the better drives on the market for Ceph journals. Some of the higher end PCIE SSDs have pretty high durability (and performance) as well, but cost more (though you can save SAS bay space, so it's a trade-off). > > Anyway, I?m curious what do the SMART counters say on your SSDs?? are they really failing due to worn out P/E cycles or is it something else? > > Cheers, Dan > > >> On 29 Sep 2014, at 10:31, Emmanuel Lacour <elacour at easter-eggs.com> wrote: >> >> >> Dear ceph users, >> >> >> we are managing ceph clusters since 1 year now. Our setup is typically >> made of Supermicro servers with OSD sata drives and journal on SSD. >> >> Those SSD are all failing one after the other after one year :( >> >> We used Samsung 850 pro (120Go) with two setup (small nodes with 2 ssd, >> 2 HD in 1U): >> >> 1) raid 1 :( (bad idea, each SSD support all the OSDs journals writes :() >> 2) raid 1 for OS (nearly no writes) and dedicated partition for journals >> (one per OSD) >> >> >> I'm convinced that the second setup is better and we migrate old setup >> to this one. >> >> Thought, statistics gives 60GB (option 2) to 100 GB (option 1) writes per day on SSD on a not >> really over loaded cluster. Samsung claims to give 5 years warranty if >> under 40GB/day. Those numbers seems very low to me. >> >> What are your experiences on this? What write volumes do you encounter, >> on wich SSD models, which setup and what MTBF? >> >> >> -- >> Easter-eggs Sp?cialiste GNU/Linux >> 44-46 rue de l'Ouest - 75014 Paris - France - M?tro Gait? >> Phone: +33 (0) 1 43 35 00 37 - Fax: +33 (0) 1 43 35 00 76 >> mailto:elacour at easter-eggs.com - http://www.easter-eggs.com >> _______________________________________________ >> 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 >
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