wp check cache size

add_action('shutdown', 'check_cache_size');

function check_cache_size() {
    global $wp_object_cache;

    $stats = array();
    foreach ($wp_object_cache->cache as $group => $cache) {
        $stats[ number_format( strlen( serialize( $cache ) ) / 1024, 2 ) ] = $group;
    }
    krsort($stats);

    ?><pre style="margin:10%;"><?php

    echo "Total cache size: " . number_format( strlen( serialize( $wp_object_cache->cache ) ) / 1024, 2 ) . "\n";

    print_r($stats);
    ?></pre><?php
}