I installed Pressflow on my Drupal 6 website by replacing core files. I only kept .htaccess, robots.txt and sites folder.
After that I got a lot of PHP errors, even after I change php.ini's error reporting.
So I checked Apache logs.
I had APC running on my site already and I noticed the following error happening frequently:
[apc-warning] Unable to allocate memory for pool.
It disappeared after I change APC memory to 16MB (it was 30MB) and restart Apache.
Although I can now load a few pages, I'm getting a white screen when trying to load home page and some other pages. Also, some regions of the page aren't showing up properly.
I tried clearing cache too.
Is there anything I'm missing?