We are using ISPConfig more than 10 years and facing problems that we never seen before. We are using same configuration (different domain but same wordpress theme + database + codes) it works pretty well. However this one is working so so slow.. We are trying to find the problem via Xdebug The problem is according to the Xdebug everything is all right. However it is not. When we simply check process runtime as follow it took 3.062 mseconds as follow. PHP: $then = microtime();myFunc();$now = microtime();echo sprintf("Elapsed: %f", $now-$then); However Xdebug shows it only took 482 mseconds. Why this difference occurs ? What causes this? We tried Debug Bar plugin etc. Nothing helped us. What is best way to find What is Slowing Down? We are using WordPress with Xdebug on following environment WordPress 5.6.2 MySQL Distrib 10.3.27-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2 Debian GNU/Linux 10 (buster) ISPConfig 3.2.2 Apache/2.4.38 (Debian) PHP 7.3.27-1~deb10u1 Zend Engine v3.3.27 with Zend OPcache v7.3.27-1~deb10u1 Our Xdebug config as follow: Code: zend_extension=/usr/lib/php/20180731/xdebug.so xdebug.remote_enable=1 xdebug.profiler_enable=1 xdebug.profiler_output_name = "cachegrind.out.%u-%H-%R.txt" xdebug.var_display_max_depth=10 xdebug.profiler_output_dir = /var/www/clients/client1/web1/web/wp-content/themes/cachegrind.out xdebug.log=10 xdebug.mode=develop,trace