On Wednesday 10 December 2008, John wrote: > On Tue, 2008-12-09 at 12:07 -0500, Ross Walker wrote: > > On Dec 9, 2008, at 10:59 AM, Matt <lm7812 at gmail.com> wrote: > > >>>> Setting scheduler is global in C4 it can be set as a kernel option > > >>>> with a scheduler=deadline in grub. > > >>> > > >>> Is that an alias for "elevator=deadline" (which I know works)? > > >> > > >> No that was me forgetting the option name. > > >> > > >> Thanks Peter, it's elevator= not scheduler= > > > > > > Does this mean I need to add "elevator=deadline" to grub.conf? Is > > > there a way to make the change without rebooting? > > > > I'm afraid not, so possibly a late night or weekend event with the > > option for a mid day reboot to recover if things turn out badly. > > > > Virtualize things and you can minimize downtime with snapshots. > > [root at blah ~]# cat /sys/block/hda/queue/scheduler > noop anticipatory deadline [cfq] > The Schedular is CFQ and can be changed on the fly to whatever Block > Device you want it. ... > [root at blah ~]# echo 'deadline' > /sys/block/hda/queue/scheduler > [root at blah ~]# cat /sys/block/hda/queue/scheduler > noop anticipatory [deadline] cfq -- Changed to Deadline. ...this is correct on CentOS-5. On CentOS-4 you need to do it via grub and a reboot. /Peter -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 189 bytes Desc: This is a digitally signed message part. URL: <http://lists.centos.org/pipermail/centos/attachments/20081210/8730f15d/attachment-0005.sig>