I have a WordPress site with 30,000+ terms for Australian cities/states. WordPress loads fine with fewer terms but 30,000 terms make it load forever.
I’ve disabled all the plugins and using the WP-2015 template. Is there a way to add such a huge number of custom terms and make the site work normally?
I have the exact same issue. It turns out the problem is the WordPress is very slow if you have many terms and the taxonomy is set to be hierarchical. Without this option the admin and frontend pages load fine.
It’s an old issue from way back which I don’t think WordPress can fix with their current database structure.
As a partial fix I improvise by making the taxonomy non hierarchical and set the parent/child relations as taxonomy meta. It only works in the front end where you have full control over the queries.
Is site slow at all places or just a set of pages? If so, which pages?
We have way more terms than you do and we have no problems. I assume that at certain places select queries take too long.
You can install plugin called Query Monitor which can show you what takes long, what triggers it and lots of other useful information which can help you locate and fix the problem
It’s old question. The issue is (as @razvan said) for hierarchical because (mainly for administration pages), WordPress create a
<select>tag for the selection of the taxonomy. But using non hierarchic taxonomies (like tags) works perfectly.