Hi,
On Wed, Nov 10, 2010 at 11:47 AM, Jeff Moyer <jmoyer@xxxxxxxxxx> wrote:
> Hi,
>
> From within the block layer in the kernel, it is difficult to
> automatically detect the performance characteristics of the underlying
> storage. It was suggested by Jens Axboe at LSF2010 that we write a udev
> rule to tune the I/O scheduler properly for most cases. The basic
> approach is to leave CFQ's default tunings alone for SATA disks. For
> everything else, turn off slice idling and bump the quantum in order to
> drive higher queue depths. This patch is an attempt to implement this.
>
> I've tested it in a variety of configurations:
> - cciss devices
> - sata disks
> - sata ssds
> - enterprise storage (single path)
> - enterprise storage (multi-path)
> - multiple paths to a sata disk (yes, you can actually do that!)
>
> The tuning works as expected in all of those scenarios. I look forward
> to your comments.
This looks useful, but I really think the kernel driver creating the
block device should choose/change the defaults for the created block
device - it seems really backwards to do this in user-space as an
afterthought.
David
--
To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
