Revisions can be a life saver when you’re editing posts but you can end up with hundreds of them if you don’t set a limit.
By adding this snippet to your wp-config.php file in the root of your WordPress installation, you can set the maximum number of revisions that will be stored for each post.
/** Post revisions. */
Remember to add the code before this line:
/* That's all, stop editing! Happy blogging. */