Caching

Compression and browser caching for WordPress in .htaccess Two of the most common PageSpeed findings, “Enable text compression” and “Serve static assets with an efficient cache policy”, are fixed on the web server, not in WordPress. On Apache hosting, which most shared WordPress hosts still use, three modules do it: mod_deflate compresses text responses, mod_expires…

Make secondary WP_Query loops cheaper: no_found_rows, cache flags and fields A default new WP_Query() does more than select posts. It also counts all matching posts for pagination (SQL_CALC_FOUND_ROWS plus SELECT FOUND_ROWS()), loads the meta of all found posts into the cache and loads their terms. For the main query of an archive that is what…

The WordPress object cache: wp_cache_set(), groups and persistent backends WordPress has a key-value cache built in. get_post(), get_option(), get_term(), user and meta lookups all store their results in it, so the same data is read from the database only once per request. Your own code can use the same cache with wp_cache_get() and wp_cache_set(). By…

Avoid N+1 queries in WordPress: prime the meta and term caches The N+1 problem: one query fetches a list of N items, and then every item in a loop makes one more query for its related data. With 50 posts that is 51 queries, with 200 posts it is 201. In WordPress it usually happens…

Simple weather in WordPress without a plugin Sometimes a site needs one or two weather values, for example the temperature or the wind speed and direction, with its own styles. A weather plugin will not help much here: it brings its own widget and markup. A small function is a better solution.

WordPress performance checklist for the end of the year The end of the year is a good moment to look at the speed of a site. Faster pages rank better, sell better and need less server. Most points of this checklist take less than an hour, and you can do them in any order; the…