Re: Article in Phoronix about loss of performance in 2.6.35 release candidates

[Ingo Molnar <mingo@elte.hu>]

* Pekka Enberg <penberg@cs.helsinki.fi> wrote:

> On Tue, Jun 1, 2010 at 7:10 AM,  <tytso@mit.edu> wrote:
> > On Tue, Jun 01, 2010 at 12:19:29AM +0100, Alex Buell wrote:
> >> http://www.phoronix.com/vr.php?view=14976
> >>
> >> Question: Why?
> >
> > One of the theories that has been advanced is that it's simply this
> > problem:
> >
> > ? ? ? ?http://lkml.org/lkml/2010/5/22/154
> >
> > If so, it points out how idiotic Phoronix is about not being able to
> > notice udev pegging the CPU at 100% being someone bad for its
> > benchmark runs. ?:-)
> >
> > OTOH, this bug has been known for over a week, and it is sort sad that
> > we haven't reverted this patch. ?It looks like the conversation has
> > died, but without a fix?
> 
> It's fixed by 1eb2cbb6d5efe129 so the problem doesn't exist for 2.6.35-r1.

Btw., the changelog in 1eb2cbb6d5efe129:

 | From 1eb2cbb6d5efe129cd006691267ce513c0aa59da Mon Sep 17 00:00:00 2001
 | From: Al Viro <viro@zeniv.linux.org.uk>
 | Date: Thu, 27 May 2010 11:11:06 -0400
 | Subject: [PATCH] Revert "anon_inode: set S_IFREG on the anon_inode"
 | 
 | This reverts commit a7cf4145bb86aaf85d4d4d29a69b50b688e2e49d.
 | ---
 |  fs/anon_inodes.c |    2 +-
 |  1 files changed, 1 insertions(+), 1 deletions(-)

Is lacking pretty much all essential pieces of information which are required 
for reverts:

 - it has no description about who reported the bug.

 - it has no description about what the problem was and what the effects were. 
   People have little chance to link up the 'udev is spinning' bug to
   this fix.

 - it has no link back to '3836a03: anon_inodes: mark the anon inode private' 
   which introduced it and hence it has no -stable tag either.

 - has no signoff line

	Ingo