lkml.org 
[lkml]   [2009]   [Apr]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 1/2] fs: mnt_want_write speedup
On Thu, Apr 02, 2009 at 11:37:20AM -0700, Dave Hansen wrote:
> On Thu, 2009-04-02 at 20:22 +0200, Nick Piggin wrote:
> > On Wed, Mar 18, 2009 at 12:13:43PM -0700, Dave Hansen wrote:
> > > On Thu, 2009-03-12 at 05:13 +0100, Nick Piggin wrote:
> > > > On Wed, Mar 11, 2009 at 03:11:17PM -0700, Dave Hansen wrote:
> > > > > I'm feeling a bit better about these, although I am still honestly quite
> > > > > afraid of the barriers. I also didn't like all the #ifdefs much, but
> > > > > here's some help on that.
> > > >
> > > > FWIW, we have this in suse kernels because page fault performance was
> > > > so bad compared with SLES10. mnt_want_write & co was I think the 2nd
> > > > biggest offender for file backed mappings (after pvops). I think we're
> > > > around parity again even with pvops.
> > >
> > > Page faults themselves? Which path was that from?
> >
> > Yes. file_update_time.
>
> We should be able to use your mnt_clone_write() optimization separate
> from the mnt_want_write() speedup here, right?

Yes that should work here.


\
 
 \ /
  Last update: 2009-04-03 03:33    [W:1.906 / U:0.192 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site