This feature works only for raid1, or both raid1 and raid5? Thanls. W ----- Original Message ----- From: "Paul Clements" <Paul.Clements@SteelEye.com> To: "3tcdgwg3" <3tcdgwg3@prodigy.net> Cc: "Stef Telford" <stef@chronozon.artofdns.com>; "'Greg Rasberry'" <rgreg-r@pacbell.net>; "'Linux raid mailing list'" <linux-raid@vger.kernel.org> Sent: Friday, May 30, 2003 1:31 PM Subject: Re: Software RAID level 1 issue > 3tcdgwg3 wrote: > > > If there is a plan to do a "intelligent resync", like some of the raid > > controller > > vendors offer? The resync process will be hold on, if there are IO requests > > from upper level, and resumed when there is no IO. By doing that, the > > system > > performance always be on the top. I am very interested in having something > > like that. > > This wasn't exactly what I meant by intelligent resync, but...I think > what you're asking about is something that the md driver already does to > some extent. It will slow down a resync if there is active I/O on the > device. This can even be tuned by the user by manipulating a couple of > kernel sysctls: > > apache:~# cat /proc/sys/dev/raid/speed_limit_min > 100 > > apache:~# cat /proc/sys/dev/raid/speed_limit_max > 10000 > > apache:~# echo 1000000 > /proc/sys/dev/raid/speed_limit_max > > apache:~# cat /proc/sys/dev/raid/speed_limit_max > 1000000 > > > These are in KB/s. > > The "min" refers to the maximum I/O bandwidth that will be consumed by > resyncs before the resyncs get throttled, when there is other I/O > activity on the device. > > The "max" refers to the maximum I/O bandwidth that will be consumed by > resyncs before the resyncs get throttled, even if there is no other I/O > activity on the device. > > -- > Paul - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
