Code profiling with Xdebug and Kcachegrind

Slides for an uncon talk I gave at phpbnl17

Transcript

1. Robert Basic ~ phpbenelux17 Code profiling with Xdebug and KCachegrind Robert Basic https://robertbasic.com/ @robertbasic
2. Robert Basic ~ phpbenelux17 Tools of the trade Xdebug • Not just for debugging KCachegrind • Visualizing profiling data
3. Robert Basic ~ phpbenelux17 What’s the fastest code?
4. Robert Basic ~ phpbenelux17 The code that’s not called!
5. Robert Basic ~ phpbenelux17 Number of calls
6. Robert Basic ~ phpbenelux17 Who’s to blame?
7. Robert Basic ~ phpbenelux17 Which was called by another method
8. Robert Basic ~ phpbenelux17 Which was called by another method
9. Robert Basic ~ phpbenelux17 So many callers!
10. Robert Basic ~ phpbenelux17 A graph to see it
11. Robert Basic ~ phpbenelux17 Context to understand it
12. Robert Basic ~ phpbenelux17 Fix it This is really up to you
13. Robert Basic ~ phpbenelux17 Tips for fixing performance issues • Biggest impact, least effort • Profile after every change • Avoid over-optimizing • Learn to EXPLAIN
14. Robert Basic ~ phpbenelux17 Tips for using Xdebug and KCachegrind • Xdebug – xdebug.profiler_output_dir – xdebug.profiler_output_name – cachegrind.out.%t.%R – Xdebug lies! • KCachegrind – Install graphviz – Use % relative – Turn on Cycle detection – Settings > Configure KCachegrind > Annotations > Add source folder
15. Robert Basic ~ phpbenelux17 Other tools • WinCacheGrind, Webgrind • XHProf • Blackfire.io
16. Robert Basic ~ phpbenelux17 Thanks! Questions?