I updated a very old Craft installation (v2.6.2794 to v2.6.2971) and now I'm locked out off the admin area. I can get to the login panel and log in but once in I just get 500 errors.
After turning on devMode, I found this:
Fatal error: Allowed memory size of 536870912 bytes exhausted (tried to allocate 72 bytes) in /mysite.com/craft/app/helpers/ModelHelper.php on line 102
I already have my phpMaxMemoryLimit
at 512M
(checked). Could my installation really be using that much memory?