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I have several WordPress (3.6) sites on the same server, all of these sites use the Memcached Object Cache - http://wordpress.org/plugins/memcached/ This plugin uses the memcache (no "d") extension.

root@linux10 [~]# php -m | grep mem

(Yep, both are installed)

root@linux10 [~]# php -v
PHP 5.4.21 (cli) (built: Oct 29 2013 12:40:13) 

2 sites work great with no issues. One particular site only works on the front end. The wp-admin fails to load with this error;

Fatal error: Class 'Memcache' not found in /home/townhous/public_html/wp-content/object-cache.php on line 372

L372 is $this->mc[$bucket] = new Memcache();

I know the object cache is working because the site uses a heavy and slow API, home page load times are 3+ seconds without the object-cache and milliseconds with the object-cache. Disabled the home page takes 3+ seconds and wp-admin works. Enabled and the homepage is fast but wp-admin doesn't work.

So, how can object-cache.php work for the front end and report a fatal error in the wp-admin?


Currently working around this issue with a nasty hack in load.php

share|improve this question
Have anyone separate it to master / slave ? – qwerty qwerty Nov 8 '13 at 12:40
No, all on the same server. – Kieran 'Kizbo' Barnes Nov 8 '13 at 16:08
As far as I googling and stacjexchanging for info, I notice that there a lot of such reports. However i suggest to crete additional host on same server and debug it (yeah you will need to use var_dump and edit scripts to see what found / what class exists etc...). that only one way to find out what a hell that was... – qwerty qwerty Nov 8 '13 at 17:41
One of the reports that you already propably saw - stackoverflow.com/questions/14795041/… – qwerty qwerty Nov 8 '13 at 17:42
Yep, saw that article, it wasn't terribly relevant. I'm going to try debugging line by line with class_exists() – Kieran 'Kizbo' Barnes Nov 8 '13 at 23:25

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