WP admin area is slow

WordPress admin slow before installing WP Rocket

WP Rocket is only able to make the front end of your site faster.

For the back end of your site, slowness could be due to a few things.

• Plugins: Some plugins will make your site slower on the backend. For example, WPML is quite notorious for making the WP admin run slow. Also, the DELUCKS SEO plugin’s stats module does intensive tracking and can blow up the database which in turn can result in very slow WP Admin and site performance, including higher TTFB values.
• WooCommerce
  - Sometimes transients cause bloat. Delete transients with our Database optimization feature.
  - Read this guide for further tips: How to Speed Up a Slow WooCommerce Backend
• Admin-ajax.php can cause slowness on both the front end and back end.
  WP Rocket indlues the Control WordPress Heartbeat API feature (HEARTBEAT tab) that can help with this.
  Control WordPress Heartbeat API
  
  If you are using an older version of WP Rocket you can either update to the latest version and use the respective WP Rocket feature or use the Heartbeat Control plugin. Read this article to learn more: http://brianjackson.io/diagnose-admin-ajax-php-causing-slow-load-times-wordpress/

Other tips for speeding up the WordPress backend:

• Use the Database tab to optimize your database. If your database gets bloated (with too many spam comments, revisions etc) it can make things slow.
• Check your error log for your server to see if there are many PHP errors from a plugin/theme
• Make sure your site has enough memory. You can try increasing the WordPress memory limit with these tips:
  http://docs.woothemes.com/document/increasing-the-wordpress-memory-limit/
• Install the Query Monitor plugin which may reveal slow scripts/database queries:
  https://wordpress.org/plugins/query-monitor/

WordPress admin slow after installing WP Rocket

While it's not a common behavior, it's possible that WordPress dashboard gets slower after installing WP Rocket, as an indirect effect of a couple of known issues.

Therefore, if disabling WP Rocket gets your dashboard to the regular speed, please check the following scenarios:

• High CPU usage caused by one of the optimization features. 
• Database Optimization feature, see more information here.
• Control WordPress Heartbeat API if the Behavior in the backend option is set to Reduce activity.
• Excessive cache clearing as expanded in this article.