WordPress revisions system saves a record of each saved draft or published update. This feature is important to site owners, because it provides some sort of “backup” for the content in case you accidentally edit posts the wrong way. By default, WordPress saves every copy of revision when you click Save button. All the revision copies take up room in database, will eventually slow down the query time, especially on sites with many blogs.
You may consider totally disable revisions feature. This can be done by adding this line into WP-CONFIG.PHP:
// Disable WordPress revisions define( 'WP_POST_REVISIONS', false );
I personally don’t recommend disabling Revisions. A WordPress post is made up of pure HTML text, for websites with handful of pages & posts, few extra copies in database won’t cause much database space, and can’t slow down post query time dramatically.
Because WordPress default setting is NO LIMIT on revisions. Reducing the number of post revisions can be a practical option. Here is the code:
// Specify a maximum number of WordPress revisions define( 'WP_POST_REVISIONS', 10 );
WordPress also autosaves post every 60 seconds. Base on your editing style, you may want to increase the setting for longer interval, or decrease the time to make sure you never lose changes.
// Specify AutoSave interval in seconds define( 'AUTOSAVE_INTERVAL', 120 );