SOLVED: Which I/O Scheduler is in Use?

[Kurt Wall]

On Thursday 26 May 2005 08:38, Man-wai Chang enlightened us thusly:
> > $ for file in `find /sys -name scheduler`
> >
> >> do
> >> echo -n "$file: "
> >> cat $file
> >> done
> >
> > /sys/block/fd0/queue/scheduler: noop anticipatory [deadline] cfq
> > /sys/block/hdd/queue/scheduler: noop anticipatory [deadline] cfq
> > /sys/block/hdc/queue/scheduler: noop anticipatory [deadline] cfq
> > /sys/block/hdb/queue/scheduler: noop anticipatory [deadline] cfq
> > /sys/block/hda/queue/scheduler: noop anticipatory [deadline] cfq
> >
> > The bracketed scheduler is the one in use.
>
> could one change it?

Yes. Pass the kernel the command line argument

elevator=<scheduler>

where <scheduler> is one of noop, anticipatory, deadline, or cfq.

Kurt