Yes, writeback mode. I didn't try anything else. Jan > On 18 Aug 2015, at 18:30, Alex Gorbachev <ag@xxxxxxxxxxxxxxxxxxx> wrote: > > HI Jan, > > On Tue, Aug 18, 2015 at 5:00 AM, Jan Schermer <jan@xxxxxxxxxxx> wrote: >> I already evaluated EnhanceIO in combination with CentOS 6 (and backported 3.10 and 4.0 kernel-lt if I remember correctly). >> It worked fine during benchmarks and stress tests, but once we run DB2 on it it panicked within minutes and took all the data with it (almost literally - files that werent touched, like OS binaries were b0rked and the filesystem was unsalvageable). > > Out of curiosity, were you using EnhanceIO in writeback mode? I > assume so, as a read cache should not hurt anything. > > Thanks, > Alex > >> If you disregard this warning - the performance gains weren't that great either, at least in a VM. It had problems when flushing to disk after reaching dirty watermark and the block size has some not-well-documented implications (not sure now, but I think it only cached IO _larger_than the block size, so if your database keeps incrementing an XX-byte counter it will go straight to disk). >> >> Flashcache doesn't respect barriers (or does it now?) - if that's ok for you than go for it, it should be stable and I used it in the past in production without problems. >> >> bcache seemed to work fine, but I needed to >> a) use it for root >> b) disable and enable it on the fly (doh) >> c) make it non-persisent (flush it) before reboot - not sure if that was possible either. >> d) all that in a customer's VM, and that customer didn't have a strong technical background to be able to fiddle with it... >> So I haven't tested it heavily. >> >> Bcache should be the obvious choice if you are in control of the environment. At least you can cry on LKML's shoulder when you lose data :-) >> >> Jan >> >> >>> On 18 Aug 2015, at 01:49, Alex Gorbachev <ag@xxxxxxxxxxxxxxxxxxx> wrote: >>> >>> What about https://github.com/Frontier314/EnhanceIO? Last commit 2 >>> months ago, but no external contributors :( >>> >>> The nice thing about EnhanceIO is there is no need to change device >>> name, unlike bcache, flashcache etc. >>> >>> Best regards, >>> Alex >>> >>> On Thu, Jul 23, 2015 at 11:02 AM, Daniel Gryniewicz <dang@xxxxxxxxxx> wrote: >>>> I did some (non-ceph) work on these, and concluded that bcache was the best >>>> supported, most stable, and fastest. This was ~1 year ago, to take it with >>>> a grain of salt, but that's what I would recommend. >>>> >>>> Daniel >>>> >>>> >>>> ________________________________ >>>> From: "Dominik Zalewski" <dzalewski@xxxxxxxxxxx> >>>> To: "German Anders" <ganders@xxxxxxxxxxxx> >>>> Cc: "ceph-users" <ceph-users@xxxxxxxxxxxxxx> >>>> Sent: Wednesday, July 1, 2015 5:28:10 PM >>>> Subject: Re: any recommendation of using EnhanceIO? >>>> >>>> >>>> Hi, >>>> >>>> I’ve asked same question last weeks or so (just search the mailing list >>>> archives for EnhanceIO :) and got some interesting answers. >>>> >>>> Looks like the project is pretty much dead since it was bought out by HGST. >>>> Even their website has some broken links in regards to EnhanceIO >>>> >>>> I’m keen to try flashcache or bcache (its been in the mainline kernel for >>>> some time) >>>> >>>> Dominik >>>> >>>> On 1 Jul 2015, at 21:13, German Anders <ganders@xxxxxxxxxxxx> wrote: >>>> >>>> Hi cephers, >>>> >>>> Is anyone out there that implement enhanceIO in a production environment? >>>> any recommendation? any perf output to share with the diff between using it >>>> and not? >>>> >>>> Thanks in advance, >>>> >>>> German >>>> _______________________________________________ >>>> 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 >>>> >>>> >>>> _______________________________________________ >>>> 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 >> _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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