WP_Upgrader::create_lock( string $lock_name, int $release_timeout = null ): bool
- Since
- 4.5.0
- Source
wp-admin/includes/class-wp-upgrader.php:1056
Compatibility
- WordPress
- since 4.5.0
- 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
$lock_namestring- The name of this unique lock.
$release_timeoutintoptional- The duration in seconds to respect an existing lock.
Default: 1 hour.Default:null
Return value
bool- False if a lock couldn't be created or if the lock is still valid. True otherwise.
Performance profile
How much work a call to WP_Upgrader::create_lock() 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
- Constant
- Instructions
- 27–41
- Plugin surface
- None
- Called by
- 3
Reaches the database via ->query().
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 51.
Nothing here hands control to plugin code.
3 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- optionoption read or write
get_option()called directly - sqldatabase query
->query()called directly - hookthird-party callbacks
apply_filters()one call below WP_Upgrader::create_lock() - cacheobject cache
wp_cache_get()one call below WP_Upgrader::create_lock() - serializeserialisation
maybe_unserialize()one call below WP_Upgrader::create_lock()
Further down the call graph this can also reach query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 4 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_Upgrader::create_lock() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 27–29 | time(), ->prepare(), ->query(), get_option() |
| always | 29–31 | time(), ->prepare(), ->query(), time(), update_option() |
$lock_result | 32–34 | time(), ->prepare(), ->query(), get_option(), time() |
!$lock_result | 39–41 | time(), ->prepare(), ->query(), get_option(), time(), ::WP_Upgrader(), ::WP_Upgrader() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 51 instructions, 27–41 executed per call, 4 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 · 4
- get_option()Retrieves an option value based on an option name.
- update_option()Updates the value of an option that was already added.
- WP_Upgrader::release_lock()Releases an upgrader lock.
- WP_Upgrader::create_lock()Creates a lock using WordPress options.
Used by · 3
- Core_Upgrader::upgrade()Upgrades WordPress core.
- WP_Automatic_Updater::run()Kicks off the background update process, looping through all pending updates.
- WP_Upgrader::create_lock()Creates a lock using WordPress options.
Source code
public static function create_lock( $lock_name, $release_timeout = null ) { global $wpdb; if ( ! $release_timeout ) { $release_timeout = HOUR_IN_SECONDS; } $lock_option = $lock_name . '.lock'; // Try to lock. $lock_result = $wpdb->query( $wpdb->prepare( "INSERT IGNORE INTO `$wpdb->options` ( `option_name`, `option_value`, `autoload` ) VALUES (%s, %s, 'off') /* LOCK */", $lock_option, time() ) ); if ( ! $lock_result ) { $lock_result = get_option( $lock_option ); // If a lock couldn't be created, and there isn't a lock, bail. if ( ! $lock_result ) { return false; } // Check to see if the lock is still valid. If it is, bail. if ( $lock_result > ( time() - $release_timeout ) ) { return false; } // There must exist an expired lock, clear it and re-gain it. WP_Upgrader::release_lock( $lock_name ); return WP_Upgrader::create_lock( $lock_name, $release_timeout ); } // Update the lock, as by this point we've definitely got a lock, just need to fire the actions. update_option( $lock_option, time(), false ); return true; }Changelog
Introduced in 4.5.0. 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 6.9.7 tag, from
src/wp-admin/includes/class-wp-upgrader.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.