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). 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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