Thousands of pages slow down dashbord page add

[C3dRy2K]

I have a website with around ~ 50k pages (post_type page) and when accessing the dashboard to add another one, the dashboard add new page loads in ~ 20s.

The heavy loading comes from Parent attribute section, where wp has to generate a insane select form tag. Couldn't we refactor this part to use a jquery autocomplete, like on non hierarchical taxonomy?

Also, the SQL query is "SELECT * FROM wp_posts ..." when as far I can see, we only need "SELECT ID, post_title FROM wp_posts ...", Time: 12.506s compare to Time: 0.507s for second query.

[SergeyBiryukov]

Hi @C3dRy2K, welcome to WordPress Trac!

Thanks for the report, we're already tracking this issue in #9864.

Related: #15459 #34982.

The heavy loading comes from Parent attribute section, where wp has to generate a insane select form tag. Couldn't we refactor this part to use a jquery autocomplete, like on non hierarchical taxonomy?

That's the idea, yes.