wp_clean_themes_cache( bool $clear_update_cache = true )
- Since
- 3.5.0
- Source
wp-includes/theme.php:142
Compatibility
- WordPress
- since 3.5.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$clear_update_cachebooloptional- Whether to clear the theme updates cache.Default:
true
Performance profile
How much work a call to wp_clean_themes_cache() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Heavy
- Scaling
- Scales with input
- Instructions
- 11–15
- Plugin surface
- None
- Called by
- 6
Reads stored settings via delete_site_option(), cached per request but not free on a cold cache.
The body loops, so the work grows with what you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 18.
Nothing here hands control to plugin code.
6 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
do_action()one call below wp_clean_themes_cache() - cacheobject cache
wp_cache_delete()one call below wp_clean_themes_cache() - optionnetwork option
delete_site_option()one call below wp_clean_themes_cache() - transienttransient
get_site_transient()one call below wp_clean_themes_cache()
Further down the call graph this can also reach serialize and query. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_clean_themes_cache() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 11–12 | search_theme_directories(), wp_get_themes() |
| always | 14–15 | delete_site_transient(), search_theme_directories(), wp_get_themes() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 18 instructions, 11–15 executed per call, 3 branches. The work does not change between versions.
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Uses · 3
- delete_site_transient()Deletes a site transient.
- search_theme_directories()Searches all registered theme directories for complete and valid themes.
- wp_get_themes()Returns an array of WP_Theme objects based on the arguments.
Used by · 6
- Theme_Upgrader::bulk_upgrade()Upgrades several themes at once.
- Theme_Upgrader::current_after()Turns off maintenance mode after upgrading the active theme.
- Theme_Upgrader::install()Install a theme package.
- Theme_Upgrader::upgrade()Upgrades a theme.
- WP_Automatic_Updater::run()Kicks off the background update process, looping through all pending updates.
- wp_clean_update_cache()Clears existing update caches for plugins, themes, and core.
Source code
function wp_clean_themes_cache( $clear_update_cache = true ) { if ( $clear_update_cache ) { delete_site_transient( 'update_themes' ); } search_theme_directories( true ); foreach ( wp_get_themes( array( 'errors' => null ) ) as $theme ) { $theme->cache_delete(); }}Changelog
Introduced in 3.5.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.1.0 tag, from
src/wp-includes/theme.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.