WordPress provides revision on page or post with 1 minutes interval auto revision / saved. This could feature could make your database become huge, so there’s a way to disable this.
Open wp-config.php located in your WordPress root directory and add the following code:
define('AUTOSAVE_INTERVAL', 300 ); // seconds define('WP_POST_REVISIONS', false );
The code will disable the revision feature and it will increase your autosave interval from 60 seconds to 300 seconds.
The above code, will not delete your past revisions that are already saved in your database. To delete all previous revisions, you will need to go to your cpanel, choose phpmyadmin and run the query below.
DELETE FROM wp_posts WHERE post_type = "revision";
This should disable Post revisions and delete all previously saved post revisions stored in your Database.