Xdebug generates profiling data compatible with Cachegrind. KCacheGrind (Linux, KDE), QCacheGrind (Windows), or WebGrind. Change force_module_rebuild to true to overwrite xdebug.ini configuration, if present, in FST/siteinfo/etc/phpXX.d/.

cd /usr/local/apnscp/resources/playbooks

ansible-playbook bootstrap.yml  --tags=php/install-extensions,apnscp/php-filesystem-template --extra-vars=pecl_extensions='{"name":"xdebug","zend":true,"extension":"https://github.com/xdebug/xdebug/archive/2.9.6.tar.gz"}' --extra-vars=force_module_rebuild=false

Add Xdebug profiling support to PHP. Depending upon configuration visibility, siteXX/fst/etc/phpXX.d/ or .user.ini are preferred.

xdebug.profiler_enable_trigger=1
xdebug.profiler_enable_trigger_value=mykey
; May want to change this...
xdebug.profiler_output_dir=/tmp

Restart the pool (or all pools) using systemctl restart php-fpm. Users may restart via Web > PHP Pools.

Visit site with ?XDEBUG_PROFILE=mykey at the end of the request URI to generate a profile at the end of the request.

systemd prefers private /tmp directories, which locates the generated cachegrind.* files in /tmp/systemd-private-HASH-php-fpm-siteXX.../tmp/. A web-accessible directory can be used instead.

PrivateTmp=no may be added to the systemd service as an override.

mkdir /var/www/html/profiler
chmod 777 /var/www/html/profiler

Adjust xdebug.profiler_output_dir accordingly.