I recently moved over to a cloud server with Westhost and installed w3-total-cache.
Every morning since the transfer my site has been down and the Westhost technical guys said this:
"From looking through your processes, it appears there is a php process that is spiking every few seconds and consuming 40 - 50 % CPU of your account. From looking through your plugins, I would suggest to disable w3-total-cache for 24 hours to see if this continues to occur."
So I deactivated w3-total-cache and sine then, my site has been fine.
Did I have an incorrect setting with the plugin to cause such a problem? Any help would be appreciated - thanks,