Runcible Blog

mod_gzip + mmcache + zlib compression = crash

I've noticed a bunch of segfaults lately in apache's log:

[Sun Jan 25 23:51:36 2004] [notice] child pid 9999 exit signal Segmentation fault (11)

I think I've tracked the problem down to too much compression. I have mod_gzip installed, but it is configured to ignore PHP files. But I did have

zlib.output_compression = On
in php.ini.

The problem was that when I installed turck-mmcache to cache compiled PHP scripts in memory/disk space, I didn't notice the


So, either PHP was trying to compress code that mmcache had already compressed, or vice versa. Either way, it lead to periodic apache segfault. But, now I have turned off zlib.output_compression since mmcache should handle the compression. It seems to speed things up quite a bit, and the gzip compression (together with mod_gzip for static pages) really helps to squeeze the most performance out of the limited upload speed I have here.

Ok, end of computer babble.

UPDATE: I may have spoken too soon. The segmentation faults continue....