Bug#328596: apache2-mpm-prefork: cgi with /usr/bin/dot keep 100% CPU for 30 sec but from shell - less than second

[Renat Sabitov <srr@stacksoft.ru>]

Package: apache2-mpm-prefork
Version: 2.0.54-5
Severity: normal

Bugzilla create graphs for bug dependences with dot. And this process is
VERY slow. For the tests i am create cgi:

$ cat /var/www/bugzilla/b.cgi 
#!/bin/bash 
echo "Content-Type: text/html"
echo
echo
echo "Start dot " `date` "<br>"
/usr/bin/dot -Tpng /tmp/test.dot -o /tmp/test.png
echo "Dot stopped " `date` "<br>"

$ cat /tmp/test.dot 
digraph G {
graph [URL="http://10.0.2.15/bugzilla/query.cgi";, rankdir=LR,
size="64,64"]
node [URL="http://10.0.2.15/bugzilla/show_bug.cgi?id=\N";, style=filled,
color=lightgrey]
288 -> 289
288 -> 290
288 -> 291
288 -> 292
291 [label="291\n",color=green]
289 [label="289\n",color=green]
292 [label="292\n",color=green]
288 [label="288\n",shape=box,color=green]
290 [label="290\n",color=green]
}

Result from web:
Start dot Fri Sep 16 14:04:16 MSD 2005
Dot stopped Fri Sep 16 14:04:34 MSD 2005 

Result from shell:
mars:~# su - www-data
www-data@mars:~$ /var/www/bugzilla/b.cgi
Content-Type: text/html


Start dot  Fri Sep 16 14:10:27 MSD 2005 <br>
Dot stopped  Fri Sep 16 14:10:27 MSD 2005 <br>


Result file test.png is same in both cases. 

$ ls -la /tmp/test.png 
-rw-r--r--  1 www-data www-data 1917 2005-09-16 14:10 /tmp/test.png

$ dpkg -S /usr/bin/dot
graphviz: /usr/bin/dot

$ dpkg -l graphviz
...skipped...
ii  graphviz                  2.2.1-1                   rich set of
graph drawing tools


-- System Information:
Debian Release: testing/unstable
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.8-2-686-smp
Locale: LANG=ru_RU.KOI8-R, LC_CTYPE=ru_RU.KOI8-R (charmap=KOI8-R) (ignored: LC_ALL set to ru_RU.KOI8-R)

Versions of packages apache2-mpm-prefork depends on:
ii  apache2-common                2.0.54-5   next generation, scalable, extenda
ii  libapr0                       2.0.54-5   the Apache Portable Runtime
ii  libc6                         2.3.5-6    GNU C Library: Shared libraries an
ii  libdb4.2                      4.2.52-18  Berkeley v4.2 Database Libraries [
ii  libexpat1                     1.95.8-3   XML parsing C library - runtime li
ii  libldap2                      2.1.30-11  OpenLDAP libraries
ii  libpcre3                      6.3-1      Perl 5 Compatible Regular Expressi
ii  libssl0.9.7                   0.9.7e-3   SSL shared libraries
ii  zlib1g                        1:1.2.2-4  compression library - runtime

apache2-mpm-prefork recommends no packages.

-- no debconf information