>>> On Sun, 30 Dec 2007 19:00:39 -0500, Brad Langhorst >>> <brad@xxxxxxxxxxxxx> said: [ ... VMware virtual disks over RAID ... ] brad> - 4 disk raid 10 brad> - 64k stripe size Stripe size or chunk size? Try reducing the chunk size if that is the chunk size, and applications in the VM do short reads or writes with intervals. But things seem not to require a lot of tweaking: [ ... ] brad> Typical blocks/sec from iostat during large file movements brad> is about 100M/s read and 80M/s write. That's fine, you are getting more or less the combined speed of 2 drives, which is what standard RAID10 over 4 drives should give you. brad> - is the partition aligned correctly? i fear not... [ brad> ... ] brad> - What should the sunit and swidth settings be during brad> mount? [ ... ] These really matter for parity RAID that do read-modify-write of unaligned sector clusters. But it is rather less essential to say the least for non-parity RAID, as it only affects speed with respect to chunk size if operations are of the order of size as the chunk size or smaller. If the applications in your VM do mostly reads, try to switch to RAID0 f2 software RAID, unless they often do concurrent reads, in which case that's a bad idea. - 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
