Re: [PATCH] Time sliced CFQ #2

From: Con Kolivas
Date: Sun Dec 05 2004 - 21:37:06 EST


Jeff Sipek wrote:
On Mon, Dec 06, 2004 at 12:59:43PM +1100, Con Kolivas wrote:
First the ioprio should be set to what the cpu 'nice' level is as a sort of global "this is the priority of this task" setting. Then it should also support changing of this priority with a different call separate from the cpu nice. That way we can take into account access privileges of the caller making it impossible to set a high ioprio if the task itself is heavily niced by a superuser and so on.


This sounds very reasonable. How would a situation like this one get
handeled:

nice = x
io_prio = y

where x!=y

then, user changes nice. Does the nice level change alone? If so,
providing some "reset to nice==io_prio" capability would make sense, no?

I think when nice is changed, ioprio needs to be changed with it as a sane default action. I suspect that most of the time people will not use the separate ioprio call, but using 'nice' is a regular linuxy thing to do. Ideally we make ioprio part of the 'nice' utility and we specify both at the same time. Something like:
nice -n 5 -i 20 blah

Cheers,
Con

Attachment: signature.asc
Description: OpenPGP digital signature