I am having a problem with an OSQA site. It is Django/Apache/mod_wsgi
configured site. Every hour, the CPU spikes to 164% (Average) for task HTTPD.
After 10 minutes, it frees back up. I have reviewed the logs, cron tables, made
many config changes, but cannot track this problem down. Can someone please look
at the information below and let me know if it is a configuration problem, or
if anyone else has experienced this issue.
Running TOP shows HTTPD using 165% of CPU
VMware performance monitor also displays spikes.
This happens every hour for 10 minutes.
I have the following information from server status
Server Version: Apache/2.2.15 (Unix) DAV/2 mod_wsgi/3.2 Python/2.6.6
Server Built: Feb 7 2012 09:50:15
Current Time: Sunday, 10-Jun-2012 21:44:29 EDT
Restart Time: Sunday, 10-Jun-2012 19:44:51 EDT
Parent Server Generation: 0
Server uptime: 1 hour 59 minutes 37 seconds
Total accesses: 1088 - Total Traffic: 11.5 MB
CPU Usage: u80.26 s243.8 cu0 cs0 - 4.52% CPU load
.152 requests/sec - 1682 B/second - 10.8 kB/request
4 requests currently being processed, 11 idle workers
....._..........__......W.......................................
...................................C._..._....._L__._L_._.......
......................
Scoreboard Key:
"_" Waiting for Connection, "S" Starting up, "R" Reading Request,
"W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup,
"C" Closing connection, "L" Logging, "G" Gracefully finishing,
"I" Idle cleanup of worker, "." Open slot with no current process
Srv PID Acc M CPU SS Req Conn Child Slot Client VHost Request
0-0 - 0/0/34 . 0.42 327 17 0.0 0.00 0.67 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
1-0 - 0/0/22 . 0.31 339 32 0.0 0.00 0.26 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
2-0 - 0/0/22 . 0.65 358 10 0.0 0.00 0.31 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
3-0 - 0/0/31 . 1.03 378 31 0.0 0.00 0.60 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
4-0 - 0/0/20 . 0.45 356 9 0.0 0.00 0.31 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
5-0 18852 0/16/34 _ 0.98 27 18120 0.0 0.37 0.62 69.180.250.36 osqa.informs.org GET /questions/289/what-is-the-difference-between-operations-re
6-0 - 0/0/32 . 0.94 309 29 0.0 0.00 0.64 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
7-0 - 0/0/31 . 1.15 382 32 0.0 0.00 0.75 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
8-0 - 0/0/21 . 0.28 403 19 0.0 0.00 0.20 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
9-0 - 0/0/32 . 1.37 288 16 0.0 0.00 0.60 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
10-0 - 0/0/33 . 1.72 383 16 0.0 0.00 0.40 127.0.0.1 osqa.informs.org OPTIONS * HTTP/1.0
I am running Django 1.3
This is a mod_wsgi configuration and copied is the wsgi.conf file:
<IfModule !python_module>
<IfModule !wsgi_module>
LoadModule wsgi_module modules/mod_wsgi.so
<IfModule wsgi_module>
<Directory /var/www/osqa>
Order allow,deny
Allow from all
#Deny from all
</Directory>
WSGISocketPrefix /var/run/wsgi
WSGIPythonEggs /var/tmp
WSGIDaemonProcess OSQA maximum-requests=10000
WSGIProcessGroup OSQA
Alias /admin_media/ /usr/lib/python2.6/site-packages/Django-1.2.5-py2.6.egg/django/contrib/admin/media/
Alias /m/ /var/www/osqa/forum/skins/
Alias /upfiles/ /var/www/osqa/forum/upfiles/
<Directory /var/www/osqa/forum/skins>
Order allow,deny
Allow from all
</Directory>
WSGIScriptAlias / /var/www/osqa/osqa.wsgi
</IfModule>
</IfModule>
</IfModule>
This is the httpd.conf file
Timeout 120
KeepAlive Off
MaxKeepAliveRequests 100
MaxKeepAliveRequests 400
KeepAliveTimeout 3
<IfModule prefork.c>
Startservers 15
MinSpareServers 10
MaxSpareServers 20
ServerLimit 50
MaxClients 50
MaxRequestsPerChild 0
</IfModule>
<IfModule worker.c>
StartServers 4
MaxClients 150
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25
MaxRequestsPerChild 0
</IfModule>
We are using MySQL
The server is an ESX4i, configured for the VM to use 4 CPUs and 8 GB Ram. Hyper threading is enabled, 2 physical CPU's, with 4 Logical. the CPU are Intel Xeon 2.8 GHz. Total memory is 12GB
