There are several causes that lead to the overcoming of resources:
 - An excessive number of visitors with respect to the plan.
 - Activities on a large website with respect to the plan.
 - Installed plugins that occupy excessive resources to the plan.
 - General overcoming resources during a request to the plan.

There are several ways how to decrease the CPU usage for your account, most efficient are these two methods:
 - If you have files that are downloaded very often (or images), we would recommend to mirror them, or host them on image / file sharing sites and only submit a link for the file in your site.
 - If your site has a database which generates a lot of load, please check the its structure and try to optimize / repair it. You can perform these actions via the cPanel -> Hosting account -> phpMyAdmin section.

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