3tcdgwg3 wrote: > > This feature works only for raid1, or both raid1 and raid5? These sysctls work for all md devices, and indeed, they apply to _all_ md devices in the system, they're not per-device. (of course, by all md devices I mean all md devices that need to do recovery...which is the raid1 and raid5 ones) -- Paul > ----- 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 - 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
