I made a reference to your work in the wiki howto on performance. Thanks! Keld On Fri, Feb 22, 2008 at 04:14:05AM +0000, Nat Makarevitch wrote: > 'md' performs wonderfully. Thanks to every contributor! > > I pitted it against a 3ware 9650 and 'md' won on nearly every account (albeit on > RAID5 for sequential I/O the 3ware is a distant winner): > http://www.makarevitch.org/rant/raid/#3wmd > > On RAID10 f2 a small read-ahead reduces the throughput on sequential read, but > even a low value (768 for the whole 'md' block device, 0 for the underlying > spindles) enables very good sequential read performance (300 MB/s on 6 low-end > Hitachi 500 GB spindles). > > What baffles me is that, on a 1.4TB array served by a box having 12 GB RAM (low > cache-hit ratio), the random access performance remains stable and high (450 > IOPS with 48 threads, 20% writes - 10% fsync'ed), even with a fairly high > read-ahead (16k). How comes?! > > - > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html