We’re currently in the process of transitioning our web servers from NetBSD to DragonflyBSD; along with that, we’re also switching our PHP platform to php-fpm. There are a few lessons we learned in the process.
First: At least on DragonflyBSD 2.10, apache2 does not at all perform well as apache-mpm-worker. Switching to apache-mpm-prefork changed our CPU load from 98% of apache to about 3-5% of apache.
Also, php-fpm was delivering too high a rate of 500 errors; this was not acceptable to our customers. Investigations into that lead me to the blog article at http://alexcabal.com/installing-apache-mod_fastcgi-php-fpm-on-ubuntu-server-maverick/#comments, which then sent me link-chasing to – ultimately – http://article.gmane.org/gmane.comp.web.fastcgi.devel/2514. This means we now have a set of local patches to our pkgsrc tree that incorporate the patch from this posting. At first sight, this seems to have improved the situation.