Your IP : 216.73.216.5
<?php
/**
* File: UsageStatistics_Sources_Apc.php
*
* @package W3TC
*/
namespace W3TC;
/**
* Class UsageStatistics_Sources_Apc
*/
class UsageStatistics_Sources_Apc {
/**
* An array that stores the names of modules.
*
* @var array
*/
private $module_names = array();
/**
* Constructor for initializing the module names from the given server descriptors.
*
* This method iterates over the provided `$server_descriptors` array and extracts the 'name'
* of each module to populate the `$module_names` array. The names are stored to keep track of
* which modules are associated with the current object instance.
*
* @param array $server_descriptors An array of server descriptors, where each descriptor is
* an associative array containing module details.
*/
public function __construct( $server_descriptors ) {
foreach ( $server_descriptors as $module_key => $i ) {
$this->module_names[] = $i['name'];
}
}
/**
* Retrieves a snapshot of the current APCu cache statistics.
*
* This method fetches the current cache information using `apcu_cache_info()` and returns
* a summary of the cache's statistics such as the number of entries, memory size, number of hits,
* and the total cache accesses (hits + misses).
*
* @return array An associative array containing the total 'items', 'size_used', 'get_hits', and 'get_total'.
*/
public function get_snapshot() {
$cache = apcu_cache_info();
return array(
'items' => $cache['num_entries'],
'size_used' => $cache['mem_size'],
'get_hits' => $cache['num_hits'],
'get_total' => ( $cache['num_hits'] + $cache['num_misses'] ),
);
}
/**
* Retrieves a summary of the APCu cache and memory statistics.
*
* This method provides a detailed summary of the cache usage, including:
* - The modules using the cache.
* - The number of cache entries.
* - The total memory used and the percentage of memory used.
* - Cache hit and miss statistics.
* - The uptime of the cache in seconds.
* - The number of cache evictions.
* - Requests per second based on the cache runtime.
*
* The method also calculates hit rate percentage and converts memory usage into a more readable format.
*
* @return array An associative array containing 'used_by', 'items', 'size_used', 'get_hits', 'get_total',
* 'runtime_secs', 'evictions', 'size_percent', 'requests_per_second', and 'get_hit_rate'
*/
public function get_summary() {
$cache = apcu_cache_info();
$time = time();
$runtime = $time - $cache['start_time'];
$mem = apcu_sma_info();
$mem_size = $mem['num_seg'] * $mem['seg_size'];
$mem_avail = $mem['avail_mem'];
$mem_used = $mem_size - $mem_avail;
$sum = array(
'used_by' => implode( ',', $this->module_names ),
'items' => $cache['num_entries'],
'size_used' => Util_UsageStatistics::bytes_to_size( $cache['mem_size'] ),
'get_hits' => $cache['num_hits'],
'get_total' => ( $cache['num_hits'] + $cache['num_misses'] ),
'runtime_secs' => $runtime,
'evictions' => $cache['expunges'],
'size_percent' => Util_UsageStatistics::percent( $mem_used, $mem_avail ),
);
if ( 0 !== $sum['runtime_secs'] ) {
$sum['requests_per_second'] = sprintf( '%.2f', $sum['get_total'] / $sum['runtime_secs'] );
}
$sum['get_hit_rate'] = Util_UsageStatistics::percent2( $sum, 'get_hits', 'get_total' );
return $sum;
}
}