[wp-trac] [WordPress Trac] #39603: The more posts with similar names you have, the slower you save the next one

WordPress Trac noreply at wordpress.org
Mon Jan 16 14:51:15 UTC 2017

#39603: The more posts with similar names you have, the slower you save the next
 Reporter:  bisyarin           |      Owner:
     Type:  defect (bug)       |     Status:  new
 Priority:  normal             |  Milestone:  Awaiting Review
Component:  Posts, Post Types  |    Version:  4.7.1
 Severity:  normal             |   Keywords:
  Focuses:  performance        |
 Hello, developers! Thank you for your work on Wordpress!

 While using Flamingo for saving Contact Form 7 submissions, I encountered
 a huge slowdown after more than 11 000 submissions had been saved. I
 thought it was a Flamingo problem, but it appears that all autogenerated
 post-types in Wordpress can cause this problem.

 Contact Form 7 saves submissions as posts with 'flamingo_inbound' type,
 and uses 'your-subject' slug when a form doesn't have a subject (which is
 my case). So, in all saved form submissions I have 'your-subject, your-
 subject-2, ..., your-subject-N' slugs generated by wp_unique_post_slug().
 The problem is that for every new 'your-subject-N' slug
 wp_unique_post_slug() issues N-1 SELECT queries. In other words,
 wp_unique_post_slug() bruteforces a new possible slug, generating a lot of
 SQL queries fetching all previously saved similar posts.

 You can see it if you run the attached 'generate-many-posts.php' script
 from your Wordpress root (more and more queries will be used for saving
 every new post).

 Also, let me suggest a solution. With the attached patch we don't
 bruteforcing the slug suffix. We just get the last appropriate slug,
 increment it's suffix, and than use this suffix in a new unique slug.

Ticket URL: <https://core.trac.wordpress.org/ticket/39603>
WordPress Trac <https://core.trac.wordpress.org/>
WordPress publishing platform

More information about the wp-trac mailing list