It was everything fine until a few days ago and my forum started to show this error:
Zend_Cache_Exception: cache_dir is not writable - library/Zend/Cache.php:209
Then I changed to front end cache today, but it makes my site really slow. A page was opening in minutes...
So I cleared all caching from config.php now it's all fine but there are no caching as you know.
How can I get rid of this problems?