WP CMS Post Control for Content Control

This is one of must-have plugins. It has been not been updated for over a year now, but it continues to work with WP 3.3.1. Hope the author/develop will continue to develop this plugin.

What does this plugin do?

gives you complete control over your write options for every user level/role in WordPress. It not only allows you to hides unwanted items like custom fields, trackbacks, revisions etc. but also gives you a whole lot more control over how WordPress deals with creating content.

Those are all nice features, but the most important feature in our opinion is the ability to completely turn off autosave and revisions.

Revisions are good for keeping track of your edited versions, but it increases database size with each revision, unnecessarily slowing down your site.

Install the plugin, then go to Settings -> WP-CMS Post Control Core Functions
check
Disable Autosave
Disable Revisions

As the disabling feature is directly related to WP Core, maybe WP developers should think of adding this feature to future versions?