Re: 2.2.15pre5, IDE and Athlon problem(s)

[Gabriele Turchi]

On Sat, Feb 05, 2000 at 11:39:42PM -0500, Mark Hahn wrote:
> > > dd if=/dev/zero of=/home/1 bs=1024k &
> 
> which is the moral equivalent to a fork-bomb: it generates an overwhelming
> stream of requests to the same region of disk.

Ehm, a simple mkisofs does a similar thing...

> 
> > It's probably a problem with the elevator sorting in
> > ll_rw_blk. I'm thinking this because the exact same
> > test doesn't give any performance hit at all on my
> > SCSI system...
> 
> I think it's merely a fairness issue with allocating request blocks;
> elevator sorting should be fine, since it's c-scan.  this isn't an issue 
> for scsi because we punt all scheduling to the disk (not always a win...)
> 
> regards, mark hahn.

I've installed Andrea's "elevator-starvation-2" patch, and was fine.
Interactive response is much better, apparently without performance losses.

Best wishes,

	Gabriele Turchi

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