Re: 2.5.46: ide-cd cdrecord success report

Jens Axboe (axboe@suse.de)
Fri, 8 Nov 2002 12:43:18 +0100


On Fri, Nov 08 2002, Ingo Oeser wrote:
> Hi Jens,
>
> On Fri, Nov 08, 2002 at 09:05:58AM +0100, Jens Axboe wrote:
> > Ok I'm just about convinced now, I'll make 16 the default batch count.
> > I'm very happy to hear that the deadline scheduler gets the job done
> > there.
>
> Isn't it exactly seek_cost, which you want?

Yes it's one request for a non-contig range, or a number of contig ones.
It isn't quite clear that this is always a good thing. Since we are
moving request from the sorted list, there's a chance that even though
serving X and then X+1 will incur a seek, it will be a small one. But
for now, yes, a seek is a seek and 16 is equal to seek_cost and
therefore it will be just the one.

> Would you like to make it tunable from user space somehow?

Yes of course, that has been the plan all along. I'm in fact doing that
right now.

> Since Adam already noticed, that there might not be a "perfect"
> value for all, this is the logical next step.

Noone ever questioned the fact that these tunables should in fact be
tunable.

> PS: If you update, please consider an update of your comments
> there, too ;-)

Patch is sent hours ago, and I did.

-- 
Jens Axboe

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