JortK

This WordPress plugin will cleanup your WordPress database, which means that it will perform the following actions:
*Remove all post revisions
*Remove all spam comments
*Remove all unapproved comments
*Remove all unused tags
*Remove all unused post meta
*Optimize MySQL tables by removing all unused table space

WP-Cleanup

This Wordpress plugin will cleanup your Wordpress database by remove all unused data from your database.

David Sader

A <a href="https://codex.wordpress.org/Create_A_Network" rel="nofollow ugc">Multisite</a> Network plugin to add Network->Settings to limit, or disable, the number of post revisions and set the post autosave interval.
<h3>Notes</h3>
I based the default plugin values for the constants AUTOSAVE_INTERVAL and WP_POST_REVISIONS on the discussion here: http://wpmututorials.com/how-to/managing-autosavepost-revisions/

Limit Post Revisions Network Option

A Multisite Network plugin to add Network Admin->Settings to limit, or disable, the number of post revisions and set the post autosave interval.

WP-Cleanup vs Limit Post Revisions Network Option