I finally fixed the memory error I was getting on my wordpress site. This is what the problem was.
I searched and searched for the answer to why this was happening to me and my site.
Allowed memory size of 268435456 bytes exhausted (tried to allocate 81 bytes) in /home1/MYSITE/public_html/wp-includes/wp-db.php on line 1775
It was always the same “answer”.
1. set memory limit to 256MB into the php5.ini
define('WP_MEMORY_LIMIT', '256M'); in wp-config.php
But, as you can see form the error I had already done that. So, I kept on reading and reading all of the posts of people complaining of the error until I found the common thread.
HOW TO FIX IT
It is, at least for me, a conflict between iThemes Security and W3 Total Cache. I don’t know what the actual conflict is, but deleting W3TC worked for me. I haven’t seen the error, which was steady, in over a month. I now use WP Fastest Cache. It isn’t as fast as W3TC, but it always allows access to my site… which seem more important.