Why does Drupal Page give me a Fatal Memory Error after switching to FastCGI with Apache2?

Question

My site was working fine until I followed this guide, http://www.howtoforge.com/how-to-set-up-apache2-with-mod_fcgid-and-php5-on-ubuntu-9.10 to set up mod_fcgid and php5.

My php.ini in every place has a memory limit of 96MB. The front page of my site (which is Panels / Views) still states, even after flushing cache, and disabling the referenced module:

Fatal error: Allowed memory size of 16777216 bytes exhausted (tried to allocate 122880 bytes) in /var/www/rvr/sites/all/modules/date/date/date.theme on line 146

However, other portions of my site still work, most notable the Drupal Tweaks module, which states my memory limit is 96MB. There are also more memory intensive portions of the site that are still working. I played around with the Boost module before doing the above guide, but its disabled, along with many modules just to try to get this back online.

I have this LAMP setup on a slicehost VPS with 386MB ram, using Ubuntu 10.04.

When I run phpinfo() in the drupal root, it states:

System  Linux Rogueroses 2.6.32.12-rscloud #26 SMP Mon May 17 12:35:34 UTC 2010 x86_64
    Build Date  May 21 2010 06:23:44
    Server API  CGI/FastCGI
    Virtual Directory Support   disabled
    Configuration File (php.ini) Path   /etc/php5/cgi
    Loaded Configuration File   /etc/php5/cgi/php.ini
    Scan this dir for additional .ini files /etc/php5/cgi/conf.d
    additional .ini files parsed    /etc/php5/cgi/conf.d/apc.ini, /etc/php5/cgi/conf.d/gd.ini, /etc/php5/cgi/conf.d/mcrypt.ini, /etc/php5/cgi/conf.d/mysql.ini, /etc/php5/cgi/conf.d/mysqli.ini, /etc/php5/cgi/conf.d/pdo.ini, /etc/php5/cgi/conf.d/pdo_mysql.ini
    PHP API 20041225
    PHP Extension   20060613
    Zend Extension  220060519
    Debug Build no
    Thread Safety   disabled
    Zend Memory Manager enabled
    IPv6 Support    enabled
    Registered PHP Streams  https, ftps, compress.zlib, compress.bzip2, php, file, data, http, ftp, zip
    Registered Stream Socket Transports tcp, udp, unix, udg, ssl, sslv3, sslv2, tls
    Registered Stream Filters   zlib.*, bzip2.*, convert.iconv.*, string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed

And further down

max_execution_time  30  30
max_file_uploads    50  50
max_input_nesting_level 64  64
max_input_time  60  60
memory_limit    96M 96M

When I'm loading a Drupal page, the top command gives this:

 6944 rvr       20   0  185m  42m  31m D    3 11.4   0:01.10 php                     
 2295 mysql     20   0  228m  24m 2128 S    0  6.7   0:57.68 mysqld     

Answer 1

96MB is low for a site with panels views and many other modules. You should increase it to maybe 150-200ish. That should give you more room to use advanced memory hungry modules.

Answer 2

While 96MB is rediculous for an average site, it is not unseen when running many modules in Drupal.

However, the error states that it went over 16M, so obviously the value as stated in your phpinfo() is not loaded correctly.

Best place to set values such as memory-limits are in the vhost configuraiton itself. Second best place is the .htaccess Third best place is in settings.php.

I assume you have either a low value (16M) in your settings.php /or/ in .htaccess. Best is to set them in the vhost config and remove them from other places.

You can see the actual values available in Drupal with devel.module, which has a simple php-info() page. Alternatively, you can create a node with PHP-parsing as filter and insert a phpinfo() there. That will show you the actual values as available in Drupal.