wp_update_post large amount of data

What do you want to update in the posts?

Sorry, I should have said what and how do you want to update the posts?

For example if you’re updating all titles to add a prefix, I would do that with a single mysql command: UPDATE wp_posts SET post_title = CONCAT(‘My Prefix ‘, post_title);

However if this is a more customized update, I would write a script that updates 10 to 20 rows, then sleeps for 1 second, then continue.

There’s nothing wrong with wp_update_post, but be aware that it will delete custom post meta if there is any.