Quentin, try fio or dd with O_DIRECT and D_SYNC flags, and you will see less than 1MB/s - that is common for most "home" drives - check the post down to understand....
We removed all Samsung 850 pro 256GB from our new CEPH installation and replaced with Intel S3500 (18.000 (4Kb) IOPS constant write speed with O_DIRECT, D_SYNC, in comparison to 200 IOPS for Samsun 850pro - you can imagine the difference...): http://www.sebastien-han.fr/blog/2014/10/10/ceph-how-to-test-if-your-ssd-is-suitable-as-a-journal-device/ Best On 4 September 2015 at 21:09, Quentin Hartman <qhart...@direwolfdigital.com> wrote: > Mine are also mostly 850 Pros. I have a few 840s, and a few 850 EVOs in > there just because I couldn't find 14 pros at the time we were ordering > hardware. I have 14 nodes, each with a single 128 or 120GB SSD that serves > as the boot drive and the journal for 3 OSDs. And similarly, mine just > started disappearing a few weeks ago. I've now had four fail (three 850 > Pro, one 840 Pro). I expect the rest to fail any day. > > As it turns out I had a phone conversation with the support rep who has > been helping me with RMA's today and he's putting together a report with my > pertinent information in it to forward on to someone. > > FWIW, I tried to get your 845's for this deploy, but couldn't find them > anywhere, and since the 850's looked about as durable on paper I figured > they would do ok. Seems not to be the case. > > QH > > On Fri, Sep 4, 2015 at 12:53 PM, Andrija Panic <andrija.pa...@gmail.com> > wrote: > >> Hi James, >> >> I had 3 CEPH nodes as folowing: 12 OSDs(HDD) and 2 SSDs (2x 6 Journals >> partitions on each SSD) - SSDs just vanished with no warning, no smartctl >> errors nothing... so 2 SSDs in 3 servers vanished in...2-3 weeks, after a >> 3-4 months of being in production (VMs/KVM/CloudStack) >> >> Mine were also Samsung 850 PRO 128GB. >> >> Best, >> Andrija >> >> On 4 September 2015 at 19:27, James (Fei) Liu-SSI < >> james....@ssi.samsung.com> wrote: >> >>> Hi Quentin and Andrija, >>> >>> Thanks so much for reporting the problems with Samsung. >>> >>> >>> >>> Would be possible to get to know your configuration of your system? >>> What kind of workload are you running? Do you use Samsung SSD as separate >>> journaling disk, right? >>> >>> >>> >>> Thanks so much. >>> >>> >>> >>> James >>> >>> >>> >>> *From:* ceph-users [mailto:ceph-users-boun...@lists.ceph.com] *On >>> Behalf Of *Quentin Hartman >>> *Sent:* Thursday, September 03, 2015 1:06 PM >>> *To:* Andrija Panic >>> *Cc:* ceph-users >>> *Subject:* Re: [ceph-users] which SSD / experiences with Samsung 843T >>> vs. Intel s3700 >>> >>> >>> >>> Yeah, we've ordered some S3700's to replace them already. Should be here >>> early next week. Hopefully they arrive before we have multiple nodes die at >>> once and can no longer rebalance successfully. >>> >>> >>> >>> Most of the drives I have are the 850 Pro 128GB (specifically >>> MZ7KE128HMGA) >>> >>> There are a couple 120GB 850 EVOs in there too, but ironically, none of >>> them have pooped out yet. >>> >>> >>> >>> On Thu, Sep 3, 2015 at 1:58 PM, Andrija Panic <andrija.pa...@gmail.com> >>> wrote: >>> >>> I really advise removing the bastards becore they die...no rebalancing >>> hapening just temp osd down while replacing journals... >>> >>> What size and model are yours Samsungs? >>> >>> On Sep 3, 2015 7:10 PM, "Quentin Hartman" <qhart...@direwolfdigital.com> >>> wrote: >>> >>> We also just started having our 850 Pros die one after the other after >>> about 9 months of service. 3 down, 11 to go... No warning at all, the drive >>> is fine, and then it's not even visible to the machine. According to the >>> stats in hdparm and the calcs I did they should have had years of life >>> left, so it seems that ceph journals definitely do something they do not >>> like, which is not reflected in their stats. >>> >>> >>> >>> QH >>> >>> >>> >>> On Wed, Aug 26, 2015 at 7:15 AM, 10 minus <t10te...@gmail.com> wrote: >>> >>> Hi , >>> >>> We got a good deal on 843T and we are using it in our Openstack setup >>> ..as journals . >>> They have been running for last six months ... No issues . >>> >>> When we compared with Intel SSDs I think it was 3700 they were shade >>> slower for our workload and considerably cheaper. >>> >>> We did not run any synthetic benchmark since we had a specific use case. >>> >>> The performance was better than our old setup so it was good enough. >>> >>> hth >>> >>> >>> >>> On Tue, Aug 25, 2015 at 12:07 PM, Andrija Panic <andrija.pa...@gmail.com> >>> wrote: >>> >>> We have some 850 pro 256gb ssds if anyone interested to buy:) >>> >>> And also there was new 850 pro firmware that broke peoples disk which >>> was revoked later etc... I'm sticking with only vacuum cleaners from >>> Samsung for now, maybe... :) >>> >>> On Aug 25, 2015 12:02 PM, "Voloshanenko Igor" < >>> igor.voloshane...@gmail.com> wrote: >>> >>> To be honest, Samsung 850 PRO not 24/7 series... it's something about >>> desktop+ series, but anyway - results from this drives - very very bad in >>> any scenario acceptable by real life... >>> >>> >>> >>> Possible 845 PRO more better, but we don't want to experiment anymore... >>> So we choose S3500 240G. Yes, it's cheaper than S3700 (about 2x times), and >>> no so durable for writes, but we think more better to replace 1 ssd per 1 >>> year than to pay double price now. >>> >>> >>> >>> 2015-08-25 12:59 GMT+03:00 Andrija Panic <andrija.pa...@gmail.com>: >>> >>> And should I mention that in another CEPH installation we had samsung >>> 850 pro 128GB and all of 6 ssds died in 2 month period - simply disappear >>> from the system, so not wear out... >>> >>> Never again we buy Samsung :) >>> >>> On Aug 25, 2015 11:57 AM, "Andrija Panic" <andrija.pa...@gmail.com> >>> wrote: >>> >>> First read please: >>> >>> http://www.sebastien-han.fr/blog/2014/10/10/ceph-how-to-test-if-your-ssd-is-suitable-as-a-journal-device/ >>> >>> We are getting 200 IOPS in comparison to Intels3500 18.000 iops - those >>> are constant performance numbers, meaning avoiding drives cache and >>> running for longer period of time... >>> Also if checking with FIO you will get better latencies on intel s3500 >>> (model tested in our case) along with 20X better IOPS results... >>> >>> We observed original issue by having high speed at begining of i.e. file >>> transfer inside VM, which than halts to zero... We moved journals back to >>> HDDs and performans was acceptable...no we are upgrading to intel S3500... >>> >>> Best >>> >>> any details on that ? >>> >>> On Tue, 25 Aug 2015 11:42:47 +0200, Andrija Panic >>> <andrija.pa...@gmail.com> wrote: >>> >>> > Make sure you test what ever you decide. We just learned this the hard >>> way >>> > with samsung 850 pro, which is total crap, more than you could >>> imagine... >>> > >>> > Andrija >>> > On Aug 25, 2015 11:25 AM, "Jan Schermer" <j...@schermer.cz> wrote: >>> > >>> > > I would recommend Samsung 845 DC PRO (not EVO, not just PRO). >>> > > Very cheap, better than Intel 3610 for sure (and I think it beats >>> even >>> > > 3700). >>> > > >>> > > Jan >>> > > >>> > > > On 25 Aug 2015, at 11:23, Christopher Kunz <chrisl...@de-punkt.de> >>> > > wrote: >>> > > > >>> > > > Am 25.08.15 um 11:18 schrieb Götz Reinicke - IT Koordinator: >>> > > >> Hi, >>> > > >> >>> > > >> most of the times I do get the recommendation from resellers to >>> go with >>> > > >> the intel s3700 for the journalling. >>> > > >> >>> > > > Check out the Intel s3610. 3 drive writes per day for 5 years. >>> Plus, it >>> > > > is cheaper than S3700. >>> > > > >>> > > > Regards, >>> > > > >>> > > > --ck >>> > > > _______________________________________________ >>> > > > 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 >>> > > >>> >>> >>> >>> -- >>> Mariusz Gronczewski, Administrator >>> >>> Efigence S. A. >>> ul. Wołoska 9a, 02-583 Warszawa >>> T: [+48] 22 380 13 13 >>> F: [+48] 22 380 13 14 >>> E: mariusz.gronczew...@efigence.com >>> <mailto:mariusz.gronczew...@efigence.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 >>> >>> >>> >>> >>> _______________________________________________ >>> 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 >>> >>> >>> >> >> >> >> -- >> >> Andrija Panić >> > > -- Andrija Panić
_______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
