Re: RFC: [PATCH] Add a sysfs entry queue/ignore_flushes.

From: Greg KH
Date: Sun Sep 11 2011 - 01:18:09 EST


On Fri, Sep 09, 2011 at 04:34:05PM -0400, Anthony DeRobertis wrote:
> I have an Oracle workload that ran quite fast under 2.6.32 due to mdraid
> not supporting barriers. 2.6.33 slowed it down very substantially, and
> its remains slow in 3.1. (Oracle is running on raw LVM logical volumes,
> not filesystems, so ext4 barrier=0 doesn't help).
>
> This patch adds a sysfs attribute to allow flush/fua to to turned off
> (ignored) on a per-block-device basis. I have tested it on both a VM and
> real hardware.
>
> I'm not sure that queue_flags is the best place to put the bit, seems
> like it may more logically go in flush_flags, but everything else is in
> queue_flags.
>
> I'm not subscribed, but will be looking for replies via list archives.
> Feel free to CC me.

If you add/remove/change sysfs attributes, you also need to do the same
to Documentation/ABI.

thanks,

greg k-h
--
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/