lkml.org 
[lkml]   [2006]   [Jan]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/2][RESEND] Default iosched fixes (was: Fall back io scheduler for 2.6.15?)
On Mon, Jan 23 2006, Nate Diller wrote:
> On 1/21/06, Jens Axboe <axboe@suse.de> wrote:
> > On Fri, Jan 20 2006, Nate Diller wrote:
> > > My previous default iosched patch did a poor job dealing with the
> > > 'elevator=' boot-time option. The old behavior falls back to the
> > > compiled-in default if the requested one is not registered at boot
> > > time. This patch dynamically evaluates which default
> > > to use, and emits a suitable error message when the requested scheduler
> > > is not available. It also does the 'as' -> 'anticipatory' conversion
> > > before elevator registration, which along with a modified registration
> > > function, allows it to correctly indicate which default scheduler is
> > > in use.
> >
> > I'm a little confused by your description - what problem does this patch
> > actually solve? We already fall back to the default, and we already do
> > the "as" conversion. It does seem to cleanup the code, just curious
> > since your description seems to promise a little more than what it
> > actually adds.
>
> It makes the ' (default)' printk that happens at elevator registration
> time behave (more) correctly. My original patch rather ignored that
> segment of code. The current behavior is to only print ' (default)'
> when one was specified at boot time, and not if 'as' was requested
> either, since it doesn't understand the 'as -> anticipatory'
> conversion. Now, it will display correctly the one selected at
> compile-time, if none was specified at boot, and when the boot-time
> option was 'as'.
>
> It also handles modular defaults better; although they cannot be
> specified in kconfig, a default requested at boot-time will now still
> work, even if it's a module. When the boot-time requested scheduler
> is not loaded, it will fall back to the compiled-in default; when it
> is, it gets used.

Ok, thanks for the (better) explanation. I'll add your patch for
inclusion, thanks.

--
Jens Axboe

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

\
 
 \ /
  Last update: 2006-01-23 22:03    [W:0.082 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site