Re: plain 2.6.21-rc5 (1) vs amanda (0)

[Gene Heskett <gene.heskett@gmail.com>]

On Sunday 01 April 2007, Gene Heskett wrote:
>On Sunday 01 April 2007, Ray Lee wrote:
>>On 3/31/07, Gene Heskett <gene.heskett@verizon.net> wrote:
>>> This effect I have isolated down to something in the 31 patches from
>>> 2.6.20.4 to 2.6.20.5-rc1, but I'm going to need additional guidance
>>> in setting up the bisect to find it.  If indeed its a kernel problem.
>>
>>First, set up a *small* test case, for your own sanity as well as
>>ours. (Set up a new backup job that does just part of your home
>>directory, for example. No, even better, just one file.) Then verify
>>that the small test case also fails the same was that you noticed your
>>big one does between 2.6.20.3 and 2.6.20.4.
>
>That will require I setup a vtape someplace else on the system.
>Later, I find the vtapes locations etc are hardcoded into the amanda
>executables, so I'm going to have to rebuild and reinstall amanda after
>copying my regular config driver to a backup version.  Not terribly
>difficult, but I will have to shut down the user amanda's crontab entry
>till we are done with the testing.  This is all part of amanda's
> security model.
>
>Ok, got that done. All logs and such will be to a different location so
> as not to disturb the normal backup once it has been resumed.  The
> disklist has been stripped down to /home.  I guess its time to reboot
> and test run.  I'll reply to this message's thread with the results.
>
>>Then, download everything in http://madrabbit.org/~ray/2.6.20.4 . That
>>has all the patches that Greg has in git, but your git is ancient so
>>let's just use the patches, hmm?
>
>My git & quilt is now the latest from the FC6 repos.
>
>>It also has a control file (called
>>'series') that lists the order they should be applied in. Save
>>everything to the root of your 2.6.20.3 source tree. It'll be messy,
>>but it'll make things easier.
>>
>>Once you have that, then go and apply the first half of the patches.
>> (As in: head -n 16 series | xargs -n 1 patch -p1
>>at the base of the tree.
>>
>>Compile and install that kernel, run your test case to see if the
>>problem is there. If it *is*, cut it in half again (Revert those 16
>>patches by adding a -R to the patch command (at the very end), then
>>redo the above command with an 8 instead of a 16.) If the problem
>>isn't there, cut the range [16,31] in half, giving you a 24 for the
>>next trial. Then repeat. Make sense?
>>
>>Ray

I haven't gotten that far yet.  A gentleman named Dave Dillow has shown me 
how to demo the problem using only tar in a scripting environment, and it 
is repeatable on a per kernel good or bad basis.
So far, the only difference that I'm seeing is in the Device: line of a 
stat . report, that first number of that line changes from good kernel to 
bad kernel.

>From another email I sent Dave an hour or so ago:

For a good kernel, 2.6.20.3-rdsl-0.31:
[root@coyote bad-kernel]# cd /usr/music
[root@coyote music]# stat .
  File: `.'
  Size: 4096            Blocks: 16         IO Block: 4096   directory
Device: fd00h/64768d    Inode: 10354963    Links: 39
Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2007-04-01 21:07:14.000000000 -0400
Modify: 2006-11-12 06:41:00.000000000 -0500
Change: 2007-01-19 13:15:22.000000000 -0500
[root@coyote music]#                                                               

Now rebooted to 2.6.21-rc5:
[root@coyote ~]# cd /usr/music
[root@coyote music]# stat .
  File: `.'
  Size: 4096            Blocks: 16         IO Block: 4096   directory
Device: ee00h/60928d    Inode: 10354963    Links: 39
Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2007-04-01 21:07:14.000000000 -0400
Modify: 2006-11-12 06:41:00.000000000 -0500
Change: 2007-01-19 13:15:22.000000000 -0500

What is this difference in the Device: line supposed to mean?

And are we 'getting warmer' here?

Thanks.

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
i dont even know if it makes sense at all :) This is an experimental patch
for an experimental kernel :))
	-- Ingo Molnar on linux-kernel