When using the pingback feature of WordPress, why does it cap the number of attempted pingbacks?

For example, if you link to multiple other posts on your own blog, it will only do one or two pingbacks per publish operation (ie when you 'publish' (and/or it goes live, if it's scheduled), or when you edit and save a published post).

It would seem that processing all pingbacks/trackbacks would be better behavior. How can that be accomplished?

When using the pingback feature of WordPress, why does it cap the number of attempted pingbacks?

For example, if you link to multiple other posts on your own blog, it will only do one or two pingbacks per publish operation (ie when you 'publish' (and/or it goes live, if it's scheduled), or when you edit and save a published post).

It would seem that processing all pingbacks/trackbacks would be better behavior. How can that be accomplished?

• pingbacks

• citation needed ;) Why do you think there is a cap, where do you see it in code or documentation? – Mark Kaplun Commented May 20, 2017 at 14:44
• @MarkKaplun - I can prove the cap by writing a blog post, and linking to more than one or two previous posts on the same site: put in five back links, and only one or two will be processed per publish attempt. – warren Commented May 20, 2017 at 15:04
• that just proves that things are not done "immediately", or that you have something that blocking the pingbacks. – Mark Kaplun Commented May 20, 2017 at 15:18
• @MarkKaplun - nothing is blocking them, as the first couple work fine. And when you do a save/republish on an existing post, the next link or two is processed. Feel free to replicate this behavior yourself. – warren Commented May 20, 2017 at 15:19
• again, that just means that you might be impatient and nothing more. – Mark Kaplun Commented May 20, 2017 at 15:20

1 Answer 1

The situation for Wordpress 5.1:

1. After publishing a post, wp-includes/post.php's _publish_post_hook() schedules the do_pings action for immediate execution. This is put into the "cron" option in database.
2. Whenever the cron job runs, do_all_pings() is executed, which sends pingbacks for all outstanding posts.
3. pingback() extracts all links from the post text and sends a pingback to each of them.

There is no limitation to 2 links anywhere.