I am using Apache/PHP/MySQL stack.
Using as framework CakePHP.
Every now and then I get a blank white page. I can't debug it through Cake, so I peek in the apache error.log and here's what I get:
[Wed Oct 12 15:27:23 2011] [notice] child pid 3580 exit signal Segmentation fault (11)
[Wed Oct 12 15:27:34 2011] [notice] child pid 3581 exit signal Segmentation fault (11)
[Wed Oct 12 15:30:52 2011] [notice] child pid 3549 exit signal Segmentation fault (11)
[Wed Oct 12 16:04:27 2011] [notice] child pid 3579 exit signal Segmentation fault (11)
zend_mm_heap corrupted
[Wed Oct 12 16:26:24 2011] [notice] child pid 3625 exit signal Segmentation fault (11)
[Wed Oct 12 17:57:24 2011] [notice] child pid 3577 exit signal Segmentation fault (11)
[Wed Oct 12 17:58:54 2011] [notice] child pid 3550 exit signal Segmentation fault (11)
[Wed Oct 12 17:59:52 2011] [notice] child pid 3578 exit signal Segmentation fault (11)
[Wed Oct 12 18:01:38 2011] [notice] child pid 3683 exit signal Segmentation fault (11)
[Wed Oct 12 22:20:53 2011] [notice] child pid 3778 exit signal Segmentation fault (11)
[Wed Oct 12 22:29:51 2011] [notice] child pid 3777 exit signal Segmentation fault (11)
[Wed Oct 12 22:33:42 2011] [notice] child pid 3774 exit signal Segmentation fault (11)
What is this segmentation fault, and how can I fix it?
UPDATE:
PHP Version 5.3.4, OSX local development
Server version: Apache/2.2.17 (Unix)
CakePhp: 1.3.10
This question is related to
php
apache
cakephp
error-logging
Attach gdb to one of the httpd child processes and reload or continue working and wait for a crash and then look at the backtrace. Do something like this:
$ ps -ef|grep httpd
0 681 1 0 10:38pm ?? 0:00.45 /Applications/MAMP/Library/bin/httpd -k start
501 690 681 0 10:38pm ?? 0:00.02 /Applications/MAMP/Library/bin/httpd -k start
...
Now attach gdb to one of the child processes, in this case PID 690 (columns are UID, PID, PPID, ...)
$ sudo gdb
(gdb) attach 690
Attaching to process 690.
Reading symbols for shared libraries . done
Reading symbols for shared libraries ....................... done
0x9568ce29 in accept$NOCANCEL$UNIX2003 ()
(gdb) c
Continuing.
Wait for crash... then:
(gdb) backtrace
Or
(gdb) backtrace full
Should give you some clue what's going on. If you file a bug report you should include the backtrace.
If the crash is hard to reproduce it may be a good idea to configure Apache to only use one child processes for handling requests. The config is something like this:
StartServers 1
MinSpareServers 1
MaxSpareServers 1
A segementation fault is an internal error in php (or, less likely, apache). Oftentimes, the segmentation fault is caused by one of the newer and lesser-tested php modules such as imagemagick or subversion.
Try disabling all non-essential modules (in php.ini), and then re-enabling them one-by-one until the error occurs. You may also want to update php and apache.
If that doesn't help, you should report a php bug.
Have you tried to increase output_buffering in your php.ini?
Source: Stackoverflow.com