Re: Cache queue_congestion_on/off_threshold

Andrew Morton
2004-05-07T03:02:34Z

"Chen, Kenneth W" <kenneth.w.chen@intel.com> wrote:
>
> >>>> Jens Axboe wrote on Wed, May 05, 2004 11:43 PM
> > On Wed, May 05 2004, Andrew Morton wrote:
> > > Jens Axboe <axboe@suse.de> wrote:
> > > >
> > > > Do you have any numbers at all for this? I'd say these calculations are
> > > > severly into the noise area when submitting io.
> > >
> > > The difference will not be measurable, but I think the patch makes sense
> > > regardless of what the numbers say.
> >
> > Humm dunno, I'd rather save the sizeof(int) * 2.
>
> Strictly speaking from memory consumption point of view, it probably comes
> for free since sizeof(struct request_queue) currently is 456 bytes on x86
> and 816 on 64bit arch. The structure is being rounded to 512 or 1024 with
> kmalloc.

That's a good argument for creating a standalone slab cache for request
queue structures ;)