Re: [BUG ext4?] Working tree getting out of date "spontaneously"

From: Björn Steinbrink <b.steinbrink@gmx.de>
Date: Jun 5, 2009, 13:21 UTC
Message-ID: <20090605132126.GB11035@atjola.homenet>
In-Reply-To: <20090605122444.GA11035@atjola.homenet>

On 2009.06.05 14:24:44 +0200, Björn Steinbrink wrote:

Show 29 quoted lines

> Hi,
> 
> can't make any sense out of this at all:
> 
> doener@atjola:git (master) $ git reset --hard HEAD@{1}
> HEAD is now at b11cf09 Merge branch 'da/pretty-tempname'
> doener@atjola:git (master) $ git update-ref refs/remotes/origin/master HEAD
> 
> doener@atjola:git (master) $ git pull
> >From git://git.kernel.org/pub/scm/git/git
>    b11cf09..6096d75  master     -> origin/master
> Updating b11cf09..6096d75
> Fast forward
>  Documentation/RelNotes-1.6.3.2.txt     |   12 +++++-------
>  Documentation/git.txt                  |    7 ++++++-
>  contrib/completion/git-completion.bash |   12 ++++++++++--
>  grep.c                                 |    6 +++++-
>  4 files changed, 26 insertions(+), 11 deletions(-)
> 
> doener@atjola:git (master) $ git diff-index --name-only HEAD
> doener@atjola:git (master) $ git diff-index --name-only --cached HEAD
> 
> *wait a minute, doing nothing*
> 
> doener@atjola:git (master) $ git diff-index --name-only HEAD
> Documentation/RelNotes-1.6.3.2.txt
> Documentation/git.txt
> contrib/completion/git-completion.bash
> grep.c

Hm, looks like this is not a git bug. Went back to 1.5.4, and even that shows the error. So I actually looked at the files, and indeed, the file in the working tree gets modified. stat(1) shows:

Right after the merge:
  File: `grep.c'
  Size: 16274           Blocks: 32         IO Block: 4096   regular file
Device: fd03h/64771d    Inode: 5933481     Links: 1
Access: (0644/-rw-r--r--)  Uid: ( 1000/  doener)   Gid: ( 1000/  doener)
Access: 2009-06-05 15:02:14.000000000 +0200
Modify: 2009-06-05 15:02:14.000000000 +0200
Change: 2009-06-05 15:02:14.000000000 +0200

60 seconds later:
  File: `grep.c'
  Size: 16274           Blocks: 32         IO Block: 4096   regular file
Device: fd03h/64771d    Inode: 5933481     Links: 1
Access: (0644/-rw-r--r--)  Uid: ( 1000/  doener)   Gid: ( 1000/  doener)
Access: 2009-06-05 15:02:14.000000000 +0200
Modify: 2009-06-05 15:02:14.000000000 +0200
Change: 2009-06-05 15:02:48.000000000 +0200

So the ctime got modified. I don't have any fancy indexing stuff running, and inotify doesn't see any events either while the ctime is changed.

The only thing I changed lately was upgrading to 2.6.30-rc8 and going from ext3 to ext4. As the ctime change always seems to happen around 30 seconds after the real change, I kind of suspect ext4 to be guilty. Ted, is that possible?

FS is mounted as: /dev/mapper/vg0-home on /home type ext4 (rw,noatime,nodiratime,barrier=0)

Björn