On Fri, Jun 22, 2007 at 10:31:32PM -0300, Henrique de Moraes Holschuh wrote: > for i in /sys/block/sd*/queue/scheduler ; do echo -n "scheduler for $i was:" > ; cat $i ; echo anticipatory > $i ; done > > Should show you the scheduler for all libata/scsi discs, and switch to > anticipatory. It probably works for hd* as well, but I don't have any > around to test. > > I had ridiculous md raid performance (on resync) using cfq at least once. > Unfortunately I never bothered trying to track it down, and I didn't check > the throughput after the resync was done either. Also, I don't recall the > kernel version, but it was either 2.6.18 or 2.6.20.
Just one kernel version? The problem here is in every kernel revision after 551c012d7eea3dc5ec063c7ff9c718d39e77634f 2.6.20-rc2,rc3,rc4,rc5,rc6,rc7 ... 2.6.20 ... 2.6.21 ... 2.6.22-rc5 noop: Timing buffered disk reads: 254 MB in 3.00 seconds = 84.66 MB/sec anticipatory: Timing buffered disk reads: 252 MB in 3.02 seconds = 83.43 MB/sec deadline: Timing buffered disk reads: 258 MB in 3.02 seconds = 85.41 MB/sec cfq: Timing buffered disk reads: 194 MB in 3.03 seconds = 64.06 MB/sec The normal value is cfq. So, all other schedulars are somewhat faster, but still far from the correct 165 MB/s. -- Carlo Wood <[EMAIL PROTECTED]> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
