* consistency problem on ZFS
@ 2013-04-28 19:11 Yann Hodique
2013-04-28 19:33 ` Thomas Rast
` (2 more replies)
0 siblings, 3 replies; 9+ messages in thread
From: Yann Hodique @ 2013-04-28 19:11 UTC (permalink / raw)
To: git
Hi,
I have a weird problem that seems to manifest itself only on ZFS
(actually the Zevo distribution, on OSX). With git 1.8.2.1 by the way.
I just switched to ZFS, so I can't blame that particular version of git.
"Sometimes" (I'd say something like 10-15% of the time, fairly
reproducible anyway), "git diff-files" will see changes that don't exist
for some time, then will catch up with the actual state of the file:
$ git checkout next; git diff-files; git checkout next; git diff-files
Already on 'next'
:100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
Already on 'next'
$
Here it was pretty quick, but sometimes I would see those phantom
diffs for more than 5 seconds.
Interestingly, if I manage to run "git diff" during that time, this one
reports no changes. See https://gist.github.com/sigma/5477827 for a more
complex trace: "git merge" was complaining about changes, yet neither "git
diff" nor "git status" did show any. That's the scenario I tried to
minimize to the invocation above.
I'm willing to accept that the filesystem has some responsibility there,
but the inconsistency bothers me. Anything I can provide to help finding
the root cause of the issue ?
Thanks for any hint (and workarounds are highly welcome, as it breaks
many of my scripts, and magit too :))
Yann.
--
A Duke must always take control of his household, for if he does not
rule those closest to him, he cannot hope to govern a planet.
-- DUKE PAULUS ATREIDES
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-28 19:11 consistency problem on ZFS Yann Hodique
@ 2013-04-28 19:33 ` Thomas Rast
2013-04-28 19:44 ` Yann Hodique
2013-04-28 20:12 ` John Szakmeister
2013-04-28 21:33 ` Junio C Hamano
2 siblings, 1 reply; 9+ messages in thread
From: Thomas Rast @ 2013-04-28 19:33 UTC (permalink / raw)
To: Yann Hodique; +Cc: git
Yann Hodique <yann.hodique@gmail.com> writes:
> I have a weird problem that seems to manifest itself only on ZFS
> (actually the Zevo distribution, on OSX). With git 1.8.2.1 by the way.
> I just switched to ZFS, so I can't blame that particular version of git.
>
> "Sometimes" (I'd say something like 10-15% of the time, fairly
> reproducible anyway), "git diff-files" will see changes that don't exist
> for some time, then will catch up with the actual state of the file:
>
> $ git checkout next; git diff-files; git checkout next; git diff-files
> Already on 'next'
> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
> Already on 'next'
> $
git-diff-files doesn't refresh the index. Why are you using it? It's
the plumbing version of 'git diff' (without args), which does the same
but *does* refresh the index.
--
Thomas Rast
trast@{inf,student}.ethz.ch
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-28 19:33 ` Thomas Rast
@ 2013-04-28 19:44 ` Yann Hodique
0 siblings, 0 replies; 9+ messages in thread
From: Yann Hodique @ 2013-04-28 19:44 UTC (permalink / raw)
To: git
>>>>> "Thomas" == Thomas Rast <trast@inf.ethz.ch> writes:
> Yann Hodique <yann.hodique@gmail.com> writes:
>> I have a weird problem that seems to manifest itself only on ZFS
>> (actually the Zevo distribution, on OSX). With git 1.8.2.1 by the way.
>> I just switched to ZFS, so I can't blame that particular version of git.
>>
>> "Sometimes" (I'd say something like 10-15% of the time, fairly
>> reproducible anyway), "git diff-files" will see changes that don't exist
>> for some time, then will catch up with the actual state of the file:
>>
>> $ git checkout next; git diff-files; git checkout next; git diff-files
>> Already on 'next'
>> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
>> Already on 'next'
>> $
> git-diff-files doesn't refresh the index. Why are you using it? It's
> the plumbing version of 'git diff' (without args), which does the same
> but *does* refresh the index.
Well, as I said, I'm mostly trying to minimize the case here (which
might or might not be successful, as it's essentially guesswork). But
whatever git-diff-files does, it seems odd that it doesn't report the
same thing twice, no ?
The actual real problem I have is the one that's exposed in the longer
trace I posted: git merge kindly asks me to fix a problem that a)
doesn't exist and b) isn't reported by porcelain commands (git diff, and
git status), and then magically stops asking after a couple of seconds.
Thanks,
Yann.
--
Battle? There's always a desire for breathing space motivating it somewhere.
-- The Bashar Teg
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-28 19:11 consistency problem on ZFS Yann Hodique
2013-04-28 19:33 ` Thomas Rast
@ 2013-04-28 20:12 ` John Szakmeister
2013-04-28 20:21 ` Yann Hodique
2013-04-28 21:33 ` Junio C Hamano
2 siblings, 1 reply; 9+ messages in thread
From: John Szakmeister @ 2013-04-28 20:12 UTC (permalink / raw)
To: Yann Hodique; +Cc: git
On Sun, Apr 28, 2013 at 3:11 PM, Yann Hodique <yann.hodique@gmail.com> wrote:
> Hi,
>
> I have a weird problem that seems to manifest itself only on ZFS
> (actually the Zevo distribution, on OSX). With git 1.8.2.1 by the way.
> I just switched to ZFS, so I can't blame that particular version of git.
>
> "Sometimes" (I'd say something like 10-15% of the time, fairly
> reproducible anyway), "git diff-files" will see changes that don't exist
> for some time, then will catch up with the actual state of the file:
>
> $ git checkout next; git diff-files; git checkout next; git diff-files
> Already on 'next'
> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
> Already on 'next'
> $
Since you're running with Mac OS X, can I ask what version? Have you
seen this with the regular file system (HFS) at all? It might be that
you need to disable core.trustctime.
-John
PS Sorry for the repeat Yann... I forgot to CC the list.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-28 20:12 ` John Szakmeister
@ 2013-04-28 20:21 ` Yann Hodique
0 siblings, 0 replies; 9+ messages in thread
From: Yann Hodique @ 2013-04-28 20:21 UTC (permalink / raw)
To: git
>>>>> "John" == John Szakmeister <john@szakmeister.net> writes:
> On Sun, Apr 28, 2013 at 3:11 PM, Yann Hodique <yann.hodique@gmail.com> wrote:
>> Hi,
>>
>> I have a weird problem that seems to manifest itself only on ZFS
>> (actually the Zevo distribution, on OSX). With git 1.8.2.1 by the way.
>> I just switched to ZFS, so I can't blame that particular version of git.
>>
>> "Sometimes" (I'd say something like 10-15% of the time, fairly
>> reproducible anyway), "git diff-files" will see changes that don't exist
>> for some time, then will catch up with the actual state of the file:
>>
>> $ git checkout next; git diff-files; git checkout next; git diff-files
>> Already on 'next'
>> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
>> Already on 'next'
>> $
> Since you're running with Mac OS X, can I ask what version? Have you
> seen this with the regular file system (HFS) at all? It might be that
> you need to disable core.trustctime.
Sure, it's OS X 10.8.3
And no, I don't see this on HFS+ at all. I've just tried numerous times
without success.
And setting core.trustctime seems to do the trick indeed. Many thanks,
that's helping a lot in the short term !
Yann.
--
At the age of fifteen, he had already learned silence.
-- from "A Child's History of Muad'Dib" by the Princess Irulan
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-28 19:11 consistency problem on ZFS Yann Hodique
2013-04-28 19:33 ` Thomas Rast
2013-04-28 20:12 ` John Szakmeister
@ 2013-04-28 21:33 ` Junio C Hamano
2013-04-29 17:55 ` Yann Hodique
2 siblings, 1 reply; 9+ messages in thread
From: Junio C Hamano @ 2013-04-28 21:33 UTC (permalink / raw)
To: Yann Hodique; +Cc: git
Yann Hodique <yann.hodique@gmail.com> writes:
> $ git checkout next; git diff-files; git checkout next; git diff-files
> Already on 'next'
> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
> Already on 'next'
> $
If you run "git update-index --refresh" between the first "checkout"
and "diff-files", do you still see the issue?
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-28 21:33 ` Junio C Hamano
@ 2013-04-29 17:55 ` Yann Hodique
2013-04-29 18:01 ` Junio C Hamano
0 siblings, 1 reply; 9+ messages in thread
From: Yann Hodique @ 2013-04-29 17:55 UTC (permalink / raw)
To: Junio C Hamano; +Cc: git
>>>>> "Junio" == Junio C Hamano <gitster@pobox.com> writes:
> Yann Hodique <yann.hodique@gmail.com> writes:
>> $ git checkout next; git diff-files; git checkout next; git diff-files
>> Already on 'next'
>> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
>> Already on 'next'
>> $
> If you run "git update-index --refresh" between the first "checkout"
> and "diff-files", do you still see the issue?
Yes, although *way* less often. I just ran a quick experiment and have
seen the issue 2 times in 2500 tries.
Thanks,
Yann.
--
There exists no separation between gods and men:
one blends softly casual into the other.
-- Proverbs of Muad'dib
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-29 17:55 ` Yann Hodique
@ 2013-04-29 18:01 ` Junio C Hamano
2013-04-29 18:16 ` Yann Hodique
0 siblings, 1 reply; 9+ messages in thread
From: Junio C Hamano @ 2013-04-29 18:01 UTC (permalink / raw)
To: Yann Hodique; +Cc: git
Yann Hodique <yann.hodique@gmail.com> writes:
>>>>>> "Junio" == Junio C Hamano <gitster@pobox.com> writes:
>
>> Yann Hodique <yann.hodique@gmail.com> writes:
>>> $ git checkout next; git diff-files; git checkout next; git diff-files
>>> Already on 'next'
>>> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
>>> Already on 'next'
>>> $
>
>> If you run "git update-index --refresh" between the first "checkout"
>> and "diff-files", do you still see the issue?
>
> Yes, although *way* less often. I just ran a quick experiment and have
> seen the issue 2 times in 2500 tries.
Hmph, that indicates somebody other than you or your Git is mucking
with the inodes of your working tree files and perphas affecting
ctime on them (we do not pay attention to atime because dirtying
cached information due to somebody else reading from the file makes
absolutely no sense, but we do notice ctime changes). Perhaps
background virus scanner or something silly like that?
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: consistency problem on ZFS
2013-04-29 18:01 ` Junio C Hamano
@ 2013-04-29 18:16 ` Yann Hodique
0 siblings, 0 replies; 9+ messages in thread
From: Yann Hodique @ 2013-04-29 18:16 UTC (permalink / raw)
To: git
>>>>> "Junio" == Junio C Hamano <gitster@pobox.com> writes:
> Yann Hodique <yann.hodique@gmail.com> writes:
>>>>>>> "Junio" == Junio C Hamano <gitster@pobox.com> writes:
>>
>>> Yann Hodique <yann.hodique@gmail.com> writes:
>>>> $ git checkout next; git diff-files; git checkout next; git diff-files
>>>> Already on 'next'
>>>> :100644 100644 bd774cccaa14e061c3c26996567ee28f4f77ec80 0000000000000000000000000000000000000000 M magit.el
>>>> Already on 'next'
>>>> $
>>
>>> If you run "git update-index --refresh" between the first "checkout"
>>> and "diff-files", do you still see the issue?
>>
>> Yes, although *way* less often. I just ran a quick experiment and have
>> seen the issue 2 times in 2500 tries.
> Hmph, that indicates somebody other than you or your Git is mucking
> with the inodes of your working tree files and perphas affecting
> ctime on them (we do not pay attention to atime because dirtying
> cached information due to somebody else reading from the file makes
> absolutely no sense, but we do notice ctime changes). Perhaps
> background virus scanner or something silly like that?
Not that I know of. I certainly don't have any virus scanner, and I even
deactivated spotlight.
In any case, I can't think of anything that would affect that volume
while leaving my HFS+ ones alone, except for zfs background
processes themselves.
Yann.
--
What senses do we lack that we cannot see or hear another world all around us?
-- The Orange Catholic Bible
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2013-04-29 18:18 UTC | newest]
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2013-04-28 19:11 consistency problem on ZFS Yann Hodique
2013-04-28 19:33 ` Thomas Rast
2013-04-28 19:44 ` Yann Hodique
2013-04-28 20:12 ` John Szakmeister
2013-04-28 20:21 ` Yann Hodique
2013-04-28 21:33 ` Junio C Hamano
2013-04-29 17:55 ` Yann Hodique
2013-04-29 18:01 ` Junio C Hamano
2013-04-29 18:16 ` Yann Hodique
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