Memory warning message I keep getting this error message:


  Warning: require_once(): Unable to allocate memory for pool. in Database::loadDriverFile() (line 1742 of /home/site/public_html/includes/database/database.inc).


I am not sure what the problem might be. It started when I installed Varnish 3.0; I couldn't get it to work, so I reverted back to my previous configuration with only APC. Now, I keep getting the message, and it is also visible to anonymous users. I have disabled the system help block from all themes, and turned off error reporting, but it still appears.

I also have mod-pagespeed enabled.
Seems to definitely be an APC issue, there's a post about it on StackOverflow which links through to a bug report on PHP.net for precisely this issue.