I have the same problem with it after upgrade.
Fatal error: Allowed memory size of 200663296 bytes exhausted (tried to allocate 20 bytes) in /home/d9642del/public_html/wp-includes/cache.php on line 537
I have reset the settings of SEO plugin to default and it was working, but then I tried to setup it from the beginning, and the error came again, even on categories archives, not just single posts.