Profile function usage

Step 1: Configure the Xdebug in profiler mode

Add the blow settings to your php.ini or if you have xdebug specific .ini file then add the below settings in that file. 

This setting is only valid for Xdebug V3.*.

xdebug.client_host=host.docker.internal
xdebug.client_port=9003
xdebug.start_with_request=yes
# Supported values for xdebug.mode are develop, debug, profile, trace etc.
# @See https://xdebug.org/docs/all_settings#mode
xdebug.mode=profile
xdebug.output_dir=/tmp
xdebug.trace_output_name=cachegrind.out.%R
xdebug.trace_format=1
xdebug.profiler_output_name=cachegrind.out.%R
xdebug.profiler_append=0
xdebug.use_compression=0

Step 2: Bind mount the /tmp folder to web container (ddev specific)

This step is ddev specific. You need to do the similar step if you are using something else.

The xdebug profiler will generate  the profiler reports in /tmp folder. We need to bind mount this /tmp folder to both web container and webgrind container so that webgrind can see the profilers files generated by xdebug in web container.

1. Create a file under .ddev/docker-compose.mount.yml
2. Add the below code to this file and save it.

services:
  web:
    # Bind mount the /tmp folder to 'web' service /tmp folder. The same /tmp
    # folder is also bind mount to 'webgrind' service. This is a way to share
    # profiler generated files between 'web' and 'webgrind' service. @See webgrind
    # service for similar bind in .ddev/docker-compose.webgrind.yml. Xdebug
    # profiler files are generated in /tmp folder. @See
    # for .ddev/php/xdebug_client_port.ini for xdebug profiler config.
    volumes:
      - type: bind
        source: /tmp
        target: /tmp
        consistency: cached

Step 3: Run the webgrind to interpret the profiler report (ddev specific)

Run the webgrind so that you can see the profiler report generated by xdebug profiler and see the function/method call counts and their time consumption. You can run 

1. Create a file under .ddev/docker-compose.webgrind.yml
2. Add the below code to this file and save it.

services:
  webgrind:
    platform: linux/x86_64
    image: jokkedk/webgrind
    container_name: "ddev-${DDEV_SITENAME}-webgrind"
    labels:
      com.ddev.site-name: ${DDEV_SITENAME}
      com.ddev.approot: ${DDEV_APPROOT}
    expose:
      - 9999
    environment:
      - VIRTUAL_HOST=$DDEV_HOSTNAME
      - HTTP_EXPOSE=9998:80
      - HTTPS_EXPOSE=9999:80
    volumes:
      # Bind mount the /tmp folder to 'webgrind' service /tmp folder. The same
      # /tmp folder is also bind mount to 'web' service. This is a way to share
      # profiler generated files between 'webgrind' and 'web' service. @See web
      # service for similar bind in .ddev/docker-compose.mount.yaml file. Xdebug
      # profiler files are generated in /tmp folder. @See
      # for .ddev/php/xdebug_client_port.ini for xdebug profiler config.
      - type: bind
        source: /tmp
        target: /tmp
        consistency: cached

Step 3: Restart the ddev and enable xdebug (ddev specific)

1. Now restart the ddev with ddev restart.
2. Enable the xdebug with ddev xdebug on . 

Steps 4: Generate the xdebug profiler reports and see in webgrind

1. If you have configured everything correctly. Now if you visit any page your profiler reports will be generated under /tmp folder with name cachegrind.out.<route> format.
2. Now you can check these profiler reports inside the webgrind by accessing the webgrind service. For ddev it will be accessible at http://<projectname>.ddev.site:9998 or https://<projectname>.ddev.site:9999
3. Now you can select the report from the dropdown in webrind and see the function/method calls and their time consumptions.
    
   
   Webgrind Screenshot
   

Known issue:

The sorting functionality of table in webgrind will not work. This is because of jquery verison being used by webgrind. This github issue should solve this problem. https://github.com/jokkedk/webgrind/pull/187