bug#36684: "View build log" - but it's empty (at first)!

bug#36684: "View build log" - but it's empty (at first)!

[Chris Marusich]

Hi,

Sometimes, I see an error like the following (it is not specific to
ant-bootstrap):

--8<---------------cut here---------------start------------->8---
$ guix package -m ~/profile-packages.scm 
...
building /gnu/store/76apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv...
| 'build' phasebuilder for `/gnu/store/76apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv' failed with exit code 1
build of /gnu/store/76apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv failed
View build log at '/var/log/guix/drvs/76/apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv.bz2'.
cannot build derivation `/gnu/store/3l11fmnyc4k1dcwlijk4vdsq70jc4lqs-icedtea-3.7.0.drv': 1 dependencies couldn't be built
killing process 20600
cannot build derivation `/gnu/store/b071r8bm2n01mp50g6r5ghxl0m09akdx-profile.drv': 1 dependencies couldn't be built
guix package: error: build of `/gnu/store/b071r8bm2n01mp50g6r5ghxl0m09akdx-profile.drv' failed
--8<---------------cut here---------------end--------------->8---

But when I try to view the log file very quickly after getting these
messages (within about 1 minute or so), I get:

--8<---------------cut here---------------start------------->8---
$ file  /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2
/var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2: empty
--8<---------------cut here---------------end--------------->8---

However, when I come back a few minutes later, mysteriously the file has
been populated:

--8<---------------cut here---------------start------------->8---
$ file  /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2 
/var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2: bzip2 compressed data, block size = 900k
--8<---------------cut here---------------end--------------->8---

Indeed, I was originally going to report that the file was empty, but
while I was writing this email, it filled up!  Is this behavior
expected?  I anticipated that the file would be finalized (empty or not)
before the helpful message "View built log at ..." was printed, but it
seems like that message is proleptic, which makes it a little confusing.

-- 
Chris

bug#36684: "View build log" - but it's empty (at first)!

[Chris Marusich]

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Chris Marusich <cmmarusich@gmail.com> writes:

> Sometimes, I see an error like the following (it is not specific to
> ant-bootstrap):
>
> $ guix package -m ~/profile-packages.scm 
> ...
> building /gnu/store/76apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv...
> | 'build' phasebuilder for `/gnu/store/76apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv' failed with exit code 1
> build of /gnu/store/76apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv failed
> View build log at '/var/log/guix/drvs/76/apf0hpcdabpjy0839nhkwgfrz3m8z5-ant-bootstrap-1.8.4.drv.bz2'.
> cannot build derivation `/gnu/store/3l11fmnyc4k1dcwlijk4vdsq70jc4lqs-icedtea-3.7.0.drv': 1 dependencies couldn't be built
> killing process 20600
> cannot build derivation `/gnu/store/b071r8bm2n01mp50g6r5ghxl0m09akdx-profile.drv': 1 dependencies couldn't be built
> guix package: error: build of `/gnu/store/b071r8bm2n01mp50g6r5ghxl0m09akdx-profile.drv' failed
>
>
> But when I try to view the log file very quickly after getting these
> messages (within about 1 minute or so), I get:
>
> $ file  /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2
> /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2: empty
>
>
> However, when I come back a few minutes later, mysteriously the file has
> been populated:
>
> $ file  /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2 
> /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2: bzip2 compressed data, block size = 900k
>
> Indeed, I was originally going to report that the file was empty, but
> while I was writing this email, it filled up!  Is this behavior
> expected?  I anticipated that the file would be finalized (empty or not)
> before the helpful message "View built log at ..." was printed, but it
> seems like that message is proleptic, which makes it a little confusing.

Whoops, I got my wires crossed.  Those build logs are for
evolution-data-server, not ant-bootstrap.  However, the same problem
holds for evolution-data-server - I built it, it failed, it said I could
find the logs at
/var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2,
it was empty at first, but then it became full.

In fact, it is only partially full, since the file ends unexpectedly:

--8<---------------cut here---------------start------------->8---
$ bzcat /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2 > /dev/null

bzcat: Compressed file ends unexpectedly;
        perhaps it is corrupted?  *Possible* reason follows.
bzcat: Success
        Input file = /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2, output file = (stdout)

It is possible that the compressed file(s) have become corrupted.
You can use the -tvv option to test integrity of such files.

You can use the `bzip2recover' program to attempt to recover
data from undamaged sections of corrupted files.

--8<---------------cut here---------------end--------------->8---

Sorry for the initial confusion, but I believe this is still a potential
issue, and I wonder if others have observed similar behavior.

-- 
Chris

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bug#36684: "View build log" - but it's empty (at first)!

[Ludovic Courtès]

Hi Chris,

Chris Marusich <cmmarusich@gmail.com> skribis:

> Whoops, I got my wires crossed.  Those build logs are for
> evolution-data-server, not ant-bootstrap.  However, the same problem
> holds for evolution-data-server - I built it, it failed, it said I could
> find the logs at
> /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2,
> it was empty at first, but then it became full.

I guess there’s a small window during which the bzip file handle hasn’t
been closed, and so you could see an empty file.  However, that window
should be extremely small: as soon as the client disconnects or the
build terminates, the daemon closes the log.

> In fact, it is only partially full, since the file ends unexpectedly:
>
> $ bzcat /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2 > /dev/null
>
> bzcat: Compressed file ends unexpectedly;
>         perhaps it is corrupted?  *Possible* reason follows.
> bzcat: Success
>         Input file = /var/log/guix/drvs/7f/n896phqyv9r636yhjipa9k4qm7g9ni-evolution-data-server-3.30.2.drv.bz2, output file = (stdout)
>
> It is possible that the compressed file(s) have become corrupted.
> You can use the -tvv option to test integrity of such files.
>
> You can use the `bzip2recover' program to attempt to recover
> data from undamaged sections of corrupted files.

So this particular log file remained truncated?

I’ve never experienced it.  Is there a scenario that allows you to
reproduce it?

Thanks,
Ludo’.

bug#36684: "View build log" - but it's empty (at first)!

[Chris Marusich]

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Ludovic Courtès <ludo@gnu.org> writes:

> I’ve never experienced it.  Is there a scenario that allows you to
> reproduce it?

I have not been able to reproduce this issue; maybe I was simply
confused when I opened the bug report.  Let's close this for now.

-- 
Chris

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