On Wed, Aug 29, 2012 at 04:34:32PM +0200, s19n wrote: > Randomly found on Google: > > http://www.jive.nl/nexpres/doku.php?id=nexpres:nexpres_wp8#tests_on_xfs_file_system > > "It is our opinion that the normalization of XFS behavior on a 24 disks > array is due to some proprietary round-robin algorithm on the raid card > that caused during the tests on a 12 disks array a 'missing disk' signal > that slowed down the pace, even though some downfalls on the 24 disks > array still happen every 18/20 files written. We ought to say that the > downfall pattern is not related to time delays or file sizes, but it is > instead a peculiarity of the XFS file system." > > Now I'd _really_ like to know if you are using a Megaraid or, as you say > at the end, a mpt2sas controller/driver, because I am going to setup a > new gluster volume with them, and considering this issue and the ext4 > one I don't really know what to choose... It's mpt2sas. I'm afraid I don't understand what exactly they are trying so say, beyond perhaps some unexpected reduction in write performance. It wouldn't concern me unduly unless my application was heavily write-intensive with the same pattern of writes as the benchmark was testing (and there is scant description of this) Regards, Brian.
