Re: [PATCH] cfq-iosched: don't allow aliased requests to starve others

From: Jens Axboe
Date: Sat Jul 24 2010 - 06:03:21 EST


On 07/24/2010 10:04 AM, Heinz Diehl wrote:
> On 14.07.2010, Jeff Moyer wrote:
>
>> Comments, as always, are welcome.
>
> This patch, applied to 2.6.35-rc6, increases desktop interactivity
> _NOTICEABLY_ on my quadcore machine, and the machine stays rock-stable.
> I have now tested this patch with the latest 2.6.35-rc kernels over
> 1 week.
>
> Unfortunately, I can't provide some testing results which makes this
> statement more objective, but I'll do some synthetic testing in the next
> days.

It is extremely unlikely that this patch will have any impact on
"normal" workloads. To even hit a code path where it would make a
difference, you would need to use O_DIRECT IO, otherwise you cannot have
aliases in the IO scheduler.

--
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/