[mwlib] mwrender error

[divadpoc]

Hy,

I just installed the render server on a Ubuntu 10.04 x64 machine
(installed in virtual box) and installed all currently available
upgrades.
Therefore I followed the instructions outlined here:
http://mwlib.readthedocs.org/en/latest/installation.html#installation-instructions-for-ubuntu-10-04-lts
Installation went smoothly w/o any problems.

When I proceed with testing the server as outlined on the same site
(http://mwlib.readthedocs.org/en/latest/installation.html#test-
install) the first command (mw-zip -c :en -o test.zip Acdc Number)
works perfectly, but when executing
# mw-render -c test.zip -o test.pdf -w rl
an error is printed:
OSError: [Errno 10] No child processes
(the whole trace is at the end)

Any ideas on how to solve this issue?
Thanks

[trace]
mw-render -c test.zip -o test.pdf -w rl
MISSING FONTS: 'AR PL UMing HK','Nazli','UnBatang','Arundina
Serif','Lohit Telugu','Sarai','Lohit Punjabi','Lohit
Oriya','AnjaliOldLipi','Kedage','LikhanNormal','Lohit Tamil','Khmer'
reading /tmp/tmp-mw-renderEQrs4s/tmpgFW6nk/revisions-1.txt
2012-06-14T11:19:43 rlwriter.info >> rendering: 'http://
en.wikipedia.org/w/index.php?title=Acdc'
2012-06-14T11:19:47 rlwriter.info >> rendering: 'http://
en.wikipedia.org/w/index.php?title=Number'
removing '/tmp/tmp-mw-renderEQrs4s/tmpgFW6nk'
Traceback (most recent call last):
File "/home/render/pp/bin/mw-render", line 9, in <module>
load_entry_point('mwlib==0.13.8', 'console_scripts', 'mw-render')
()
File "/home/render/pp/lib/python2.6/site-packages/mwlib/apps/
render.py", line 235, in main
return Main()()
File "/home/render/pp/lib/python2.6/site-packages/mwlib/apps/
render.py", line 200, in __call__
writer(env, output=tmpout, status_callback=self.status,
**writer_options)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 2188, in writer
r.writeBook(output=output, coverimage=coverimage,
status_callback=status_callback)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 480, in writeBook
art_elements = self.writeArticle(art)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 811, in writeArticle
elements.extend(self.renderMixed(article))
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1090, in renderMixed
res = self.write(c)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 335, in write
res = m(obj)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 662, in writeSection
elements.extend(self.renderMixed(obj))
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1090, in renderMixed
res = self.write(c)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 335, in write
res = m(obj)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1731, in writeCenter
return self.renderMixed(n, text_style(mode='center',
in_table=self.table_nesting))
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1090, in renderMixed
res = self.write(c)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 335, in write
res = m(obj)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 2039, in writeTable
self.getTableSize(t)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 2004, in getTableSize
t.min_widths, t.max_widths = self._getTableSize(t)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1982, in _getTableSize
content = self.renderCell(cell)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1887, in renderCell
elements.extend(self.renderMixed(cell,
text_style(in_table=self.table_nesting, text_align=align)))
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 1090, in renderMixed
res = self.write(c)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 335, in write
res = m(obj)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/rl/
rlwriter.py", line 2114, in writeMath
imgpath = writerbase.renderMath(source, output_path=self.tmpdir,
output_mode='png', render_engine='texvc', resolution_in_dpi=density)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/
mathutils.py", line 139, in renderMath
result = _renderMathTexvc(latex, output_path=output_path,
output_mode=output_mode, resolution_in_dpi=resolution_in_dpi)
File "/home/render/pp/lib/python2.6/site-packages/mwlib/
mathutils.py", line 91, in _renderMathTexvc
(result, error) = sub.communicate()
File "/usr/lib/python2.6/subprocess.py", line 701, in communicate
return self._communicate(input)
File "/usr/lib/python2.6/subprocess.py", line 1246, in _communicate
self.wait()
File "/usr/lib/python2.6/subprocess.py", line 1170, in wait
pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
File "/usr/lib/python2.6/subprocess.py", line 465, in
_eintr_retry_call
return func(*args)
OSError: [Errno 10] No child processes
[/trace]

[Ralf Schmitt]

divadpoc <david.po...@gmail.com> writes:

> # mw-render -c test.zip -o test.pdf -w rl
> an error is printed:
> OSError: [Errno 10] No child processes
> (the whole trace is at the end)

did you install texvc? can you show us the output of
strace mw-render -c test.zip -o test.pdf -w rl ?

[Noeon]

Hi there!

I get the same error on Debian 6.0.5.

I followed the instructions outlined here. Installation of texvc included.
http://mwlib.readthedocs.org/en/latest/installation.html#installation-instructions-for-ubuntu-10-04-lts

I used the following commands to test the installation:

mw-zip -c :en -o test.zip Acdc Number

This works without any problems.

mw-render -c test.zip -o test.pdf -w rl

This throws an error: OSError: [Errno 10] No child processes

Enclosed you will find the output of "strace mw-render -c test.zip -o test.pdf -w rl".

(strace.txt)

Any idea?

Thanks and greetings.

[David Pocivalnik]

yes, installed texvc, as written in the online guide for installing on
ubuntu 10.04.
i can't send u any traces anymore as I switched to 12.04 where I didn't
get the error anymore. (installation works way smoother with 12.04)

br


--
David Pocivalnik
http://www.pocivalnik.com/emaildisclaimer.php

[David Pocivalnik]

hy,

i switched to Ubuntu 12.04 LTS x64 server and it worked w/ the guide for
ubuntu 10.04. Just some additional links for libraries as python
searches in different location (jpeg, zip lib).

hope you can resolve the error though!

best regards

On 06/23/2012 12:59 PM, Noeon wrote:
> Hi there!
>
> I get the same error on Debian 6.0.5.
>
> I followed the instructions outlined here. Installation of texvc included.
> http://mwlib.readthedocs.org/en/latest/installation.html#installation-instructions-for-ubuntu-10-04-lts
>
> I used the following commands to test the installation:
>
> mw-zip -c :en -o test.zip Acdc Number
>
> This works without any problems.
>
> mw-render -c test.zip -o test.pdf -w rl
>

> This throws an error: *OSError: [Errno 10] No child processes*

>
> Enclosed you will find the output of "strace mw-render -c test.zip -o
> test.pdf -w rl".
> (strace.txt)
>
> Any idea?
> Thanks and greetings.
>
>
>
> Am Donnerstag, 21. Juni 2012 15:02:00 UTC+2 schrieb Ralf Schmitt:
>>
>> divadpoc <david.po...@gmail.com> writes:
>>
>>> # mw-render -c test.zip -o test.pdf -w rl
>>> an error is printed:
>>> OSError: [Errno 10] No child processes
>>> (the whole trace is at the end)
>>
>> did you install texvc? can you show us the output of
>> strace mw-render -c test.zip -o test.pdf -w rl ?
>>
>

[Ralf Schmitt]

Noeon <no...@me.com> writes:

> Hi there!
>
> I get the same error on Debian 6.0.5.
>
> I followed the instructions outlined here. Installation of texvc included.
> http://mwlib.readthedocs.org/en/latest/installation.html#installation-instructions-for-ubuntu-10-04-lts
>
> I used the following commands to test the installation:
>
> mw-zip -c :en -o test.zip Acdc Number
>
> This works without any problems.
>
> mw-render -c test.zip -o test.pdf -w rl
>

> This throws an error: *OSError: [Errno 10] No child processes*
>

> Enclosed you will find the output of "strace mw-render -c test.zip -o
> test.pdf -w rl".
> (strace.txt)
>
> Any idea?

Thanks for sending the strace output. It contains the following:

,----
| write(1, "\33[K38.0% laying out Number\r", 27) = 27
| ...
| clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f6adf0ae9d0) = 2039
| ...
| wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], WNOHANG|WSTOPPED|WCONTINUED, NULL) = 2039
| ...
| wait4(2039, 0x7fffeb29ded4, 0, NULL) = -1 ECHILD (No child processes)
`----

which means it's trying two times to get the return status of the child
process. This looks like it may be an issue with gevent, which started
reaping child processes some time ago.

I'll try to reproduce the issue and fix it.

--
Cheers
Ralf

[Ralf Schmitt]

Ralf Schmitt <ra...@brainbot.com> writes:

>
> ,----
> | write(1, "\33[K38.0% laying out Number\r", 27) = 27
> | ...
> | clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f6adf0ae9d0) = 2039
> | ...
> | wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], WNOHANG|WSTOPPED|WCONTINUED, NULL) = 2039
> | ...
> | wait4(2039, 0x7fffeb29ded4, 0, NULL) = -1 ECHILD (No child processes)
> `----
>
> which means it's trying two times to get the return status of the child
> process. This looks like it may be an issue with gevent, which started
> reaping child processes some time ago.
>
> I'll try to reproduce the issue and fix it.

Upgrading gevent to the latest version will fix it. The following
command does that:

,----
| PIP_INDEX_URL=http://pypi.pediapress.com/simple/ pip install -U gevent
`----

--
Cheers
Ralf

[Noeon]

Hi Ralf,

works like a charm.

Thanks for your help!

Greetings.

Peter