Performance/Fenix/Profilers and Tools: Difference between revisions

# The '''Firefox Profiler / Gecko Profiler''' ([https://profiler.firefox.com/docs/#/./guide-remote-profiling documentation]) is the preferred profiler. This profiler allows us to profile the code with lower overhead and non-debuggable builds including APKs from the Play Store, capture native code, and share profiles right in the browser. The UX is just so much better. :) You should try another profiler if you:

## Need access to Java threads other than the main thread (issue )

## Are profiling application start up and some information is missing ([https://bugzilla.mozilla.org/show_bug.cgi?id=1659103 bug 1659103])

#The '''Android Profiler''' ([https://developer.android.com/studio/profile/android-profiler/?gclid=EAIaIQobChMImNycnqrf6gIVUfDACh3PWQe6EAAYASAAEgIb6_D_BwE&gclsrc=aw.ds documentation]) is most useful when you:  

##Need access to Java threads other than the main thread  

##Are profiling application start up and want to capture it as early as possible

#: The results in the Android Profiler are '''very misleading''': what you see in profiles may not accurately represent what users’ experience in release builds. This is due to the debuggable=true requirement which causes different methods to  increase in runtime inconsistently ([https://youtu.be/ZffMCJdA5Qc?t=631 further explanation]). For example, in the AS Profiler, we’ve seen that UI layout is proportionally longer than business logic than in production builds.

#'''Simpleperf''' ([https://android.googlesource.com/platform/system/extras/+/master/simpleperf/doc/README.md#Android-application-profiling official documentation]; follow the Fenix-specific steps found in this [https://github.com/acreskeyMoz/simpleperf_for_geckoview_example#simpleperf-for-gecko-apps README]) is most useful when you:

##Need access to Java threads other than the main thread

##Are profiling application start up and want to capture it as early as possible

#:This is a good alternative to the AS profiler since it has a much lower overhead. However, it’s difficult to set up and will only be able to profile start up with rooted phones.

#'''Nanoscope''' is another tool that can be useful to profile non-debuggable applications. ([https://github.com/acreskeyMoz/simpleperf_for_geckoview_example#simpleperf-for-gecko-apps documentation]). We would only suggest to use this tool whenever profiling start up has failed with the previous options.