A quick overview of how to get started visualizing your Drupal (or PHP in general, or whatever language) code. Helpful for learning complicated systems, finding performance bottlenecks, and feeling cool.

1. VISUALIZING DRUPAL CODE

2. OUTLINE
 Why? / The Benefit
 How to get setup
 Limitations and ass-umptions
 Discuss other available tools

3. WHY? / THE BENEFIT
 Get a bird’s eye view of important Drupal Subsystems like Views,
Theme, Entity API, Forms API, etc… before you get buried in
never-ending callstacks.
 See which parts of a system take the longest so you can focus
your limited time where it will have the most impact.
 Quickly refresh memory about an area you haven’t been in for a
while.
 Use to analyze system for understanding, bug fixing, etc… Easier
for multiple people to think about something together.

4. HOW TO GET SETUP
 Tools you’ll need:
 Xdebug
 PHPStorm setup: https://www.jetbrains.com/phpstorm/help/configuring-xdebug.html
 Netbeans setup: http://wiki.netbeans.org/HowToConfigureXDebug
 Need one extra config setting in your php.ini to output a profiler/cachegrind file
 http://www.xdebug.org/docs/profiler
 This is the dumped data used to create the visualizations
 CacheGrind (different versions for Mac, Win, Linux)
 Find the version for your platform, also here: http://www.xdebug.org/docs/profiler
 For Mac: https://langui.sh/2011/06/16/how-to-install-qcachegrind-kcachegrind-on-
mac-osx-snow-leopard/

5. VISUALIZE THE CALL STACK
 On localhost, with the correct xdebug.profiler_enable settings,
load a page.
 This generates a cachegrind.out.nnn file in your /tmp directory.
 Open qcachegrind and load the cachegrind.out.nnn file
 BOOM BABY!
 Let’s look at it live.

6. LIMITATIONS
 The visualization doesn’t portray time/sequence.
 Good article, “How Profilers Lie.”
 http://yosefk.com/blog/how-profilers-lie-the-cases-of-gprof-and-
kcachegrind.html

7. OTHER AVAILABLE TOOLS
 Kazanir mentioned blackfire: http://blackfire.io/
 XHProf – not familiar with how this is different from what you get
with xdebug.
 NewRelic has a little overlap as far as finding bottlenecks –
awesome tool I wouldn’t want to live without.