Ming Zhang <mingz@xxxxxxxxxxx> writes: > have u try the parallel write? I haven't tested it as thoroughly, as it brings lvm and the filesystem into the mix. (The disks are in "production" use, and are fairly full, so I can't do writes directly to the disk partitions/raid device.) My preliminary finding is that raid writes are faster than non-raid writes: 49MB/s vs 39MB/s. Still not stellar performance, though. Question for the list: if I'm doing a long sequential write, naively each parity block will get recalculated and rewritten several times, once for each non-parity block in the stripe. Does the write-caching that the kernel does mean that each parity block will only get written once? Dan - 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
