[horde] Apache / PHP / Horde server memory usage

[Simon Wilson]

OK, I have set up a new virtual server to try Horde4. I am having  
problems with memory usage.

This is an export of xm list on the host:

Name                                      ID Mem(MiB) VCPUs State   Time(s)
Domain-0                                   0      512     2 r-----   5009.8
server01                                   1      256     1 -b----    517.2
server02                                   2      896     1 -b----    382.1
server03                                   3     1536     1 -b----   1255.1
server04                                   4     2048     1 -b----   1811.0
server05                                   5     1408     1 -b----    689.5
server06                                   6     1280     1 ------   6728.0

Servers 1 to 6 were all started at the same time. Server04 is my mail  
server - IMAP, Horde3, Postfix, amavisd, etc, and is usually the  
busiest by far. Yet notice the huge difference in Time consumed by the  
Horde web server.

Server06 is Horde4 on Apache 2.2.3, php 5.2.10, and nothing else. It's  
based on the same CentOS 5.6 x64 template xen server that each of the  
others is, and is up to date. Everything has been "yum"ed from core  
CentOS repos except php from CentOS testing, a bacula client, webmin,  
and the horde pear and pecl requirements as needed to get Horde4 going.

Httpd memory usage just climbs steadily, and then within 24 hours, the  
server runs out of memory, both real and swap.

It has 1.25GB real RAM assigned to it, and 512 MB swap. Restarting  
httpd brings it back to life (although takes a few minutes to  
accomplish) when it then uses < 250MB mem, and 0 swap. Server04 has  
2GB real, and the same size 512MB swap which it never touches.

All I see in logs as 06 runs out of memory are lots of oom-killer  
messages, followed by Horde dying...

[Tue May 24 19:01:33 2011] [error] [client 192.168.1.155] PHP Fatal  
error:  Maximum execution time of 30 seconds exceeded in  
/usr/share/pear/Horde/Autoloader.php on line 66

then lots of these:

[Tue May 24 19:52:37 2011] [warn] child process 28421 still did not  
exit, sending a SIGTERM

I had php set to 128MB, have pulled it back to 64MB to see how it goes.

I had noticed that imagick was killing httpd memory usage, but  
disabled image manipulation yesterday completely.

I can set a trap for memory levels to restart httpd, but seems odd to  
have to. Anyone else having memory issues, or make suggestions on  
keeping my Horde web server alive?

Simon

-- 
Simon Wilson