On 5/27/14 13:40 , phowell wrote: > Hi > > First apologies if this is the wrong place to ask this question. > > We are running a small Ceph (0.79) cluster will about 12 osd's which > are on top of a zfs raid 1+0 (for another discussion)... which were > created on this version. > Just a reminder to benchmark everything, especially things you have known to be true since the dawn of time. I benchmarked RAID10 vs. RAID5 so long ago, I had to find a 3.5" floppy to open the spreadsheet. Recently, I was testing ZFS on software encrypted volumes, and wanted to see how badly it would impact a PostgreSQL server. My test setup was using RAIDZ2, so I just ran the benchmark on that zpool. Imagine my surprise when an untuned and encrypted RAIDZ2 posted better benchmarks than a tuned ZFS RAID10. I really think the "RAID5 is bad for performance" is a nasty hold-over from when parity calculations needed dedicated hardware. I won't be building any more ZFS RAID10 arrays. -- *Craig Lewis* Senior Systems Engineer Office +1.714.602.1309 Email clewis at centraldesktop.com <mailto:clewis at centraldesktop.com> *Central Desktop. Work together in ways you never thought possible.* Connect with us Website <http://www.centraldesktop.com/> | Twitter <http://www.twitter.com/centraldesktop> | Facebook <http://www.facebook.com/CentralDesktop> | LinkedIn <http://www.linkedin.com/groups?gid=147417> | Blog <http://cdblog.centraldesktop.com/> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20140527/7062c7bd/attachment.htm>
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