Improve performance Search REST API

[furi3r]

Search query rest endpoint will make a query per post_id for each post in the result.
A possible solution, Prime_post_cache needed.
​https://github.com/WordPress/wordpress-develop/blob/4558de543c64c877ffea4cdfbdf67d743c3e4391/src/wp-includes/rest-api/search/class-wp-rest-post-search-handler.php#L86

[furi3r]

api query result

[furi3r]

working on it.

Trac ticket: #55674

Why was limiting the fields to ids avoided to fetch the whole post data and then pluck the ids?

@namithj

Why was limiting the fields to ids avoided to fetch the whole post data and then pluck the ids?

Doing a query for the entire post object will warm the object cache for the get_post() function calls in the prepare_item() method. This prevents an additional database query for each found post.

You raise a good point though, it's probably worth adding a comment explaining this in the code so a future developer doesn't change the query and cause extra database queries.

[furi3r]

Query result before patch

[furi3r]

Query result after patch

[furi3r]

See attachment, before and after applying the patch, we save one query per result, and the time is considerably reduced.
For a 6 items result:
27 VS 22 queries.
0.0171s VS 0.0146s

[spacedmonkey]

@audrasjb Are you good to commit this. It as been approved by two core committers ( me included ).

[audrasjb]

Reassigned to @spacedmonkey who is taking care of this ticket from the beginning :)

[spacedmonkey]

In 53485:

REST API: Improve post cache priming in WP_REST_Post_Search_Handler class.

In the WP_REST_Post_Search_Handler class, ensure that post, post meta and term caches are correctly primed when performing a search.

Props furi3r, spacedmonkey, TimothyBlynJacobs, audrasjb, peterwilsoncc.
Fixes #55674.

Committed.

[desrosj]

In 53676:

Coding Standards: Apply some alignment fixes after composer format.

Follow up to [53485].

See #55674.

[desrosj]

There are a lot of caching related changes in 6.1 and a dev note should be written collecting them all. Marking this for inclusion.

[spacedmonkey]

Early draft of a dev note can be found ​here.

[milana_cap]

Dev note: ​https://make.wordpress.org/core/2022/10/10/performance-improvements-to-the-rest-api/