On Sat, Jun 11, 2011 at 04:27:02PM -0400, Mikulas Patocka wrote: > It is much easier to explain to the users "if you set X value in > /sys/module/dm_mirror/parameters/raid1_resync_throttle, then the copying > will be done in X% of time, leaving the disk idle 100-X% of time", then to > invent some magic mechanisms that change multiple things based on X and > other conditions. Yes, that is very easy to explain to the users. This sort of description is what I was after when I kept asking you to tell me how to set it. It's not clear to me that setting the throttle to 80% will copy at 80% of the speed, or leave the disk idle for 20% of the time. Perhaps you have some benchmarks to back this up? (with different memory pressure situations please). Restricting the cpu available to issue io is not a great way to throttle io. There will be plenty of situations where 20% of the cpu is enough to swamp the devices. - Joe -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
