[Plugin: WP Super Cache] Major problem – site stops loading intermittently

I’m having a major problem.

Supercache seems to work ok, but after some amount of time (3-6 hours?), my site stops working… basically, it never comes up. I will often get database errors (could not connect).

if I go in & delete all the cached files, it works again… until it does again hours later.

what the…? I really need to fix this as my site keeps failing to come up