I want to profile the startup of an app. The goal is to see where things like layout and paint might block startup to see if we need some new APIs to turn off these things while the app JS is generating the starting view, related to this dev-platform thread[1].
How do people do that sort of profiling today? It is my understanding raptor is not the tool for that, and the profile.sh script should be used. I did a build and can run profile.sh via the instructions on MDN[2]. I can get captures from running processes, but since I want to profile the startup of a webapp[3], using `start -p [name]` is not the way to go, since the pid cannot be not known when the app is closed. Using `./profile.sh start` with no other arguments restarts the device, but goes to a black screen and is not operable. The MDN page also indicates this mode of profile.sh is deprecated. The last lines in the logcat when this happens: I/ServiceManager( 190): service 'android.security.keystore' died I/ServiceManager( 190): service 'SurfaceFlinger' died I/ServiceManager( 190): service 'permission' died I/ServiceManager( 190): service 'display.qservice' died I/Gecko ( 2712): [Child 2712] WARNING: pipe error (3): Connection reset by peer: file /home/jr/git/B2G/gecko/ipc/chromium/src/chrome/common/ipc_channel_posix.cc, line 459 I/Gecko ( 2712): I/Gecko ( 2712): ###!!! [Child][MessageChannel::SendAndWait] Error: Channel error: cannot send/recv I tried the WebIDE's profiling tool and clicking the reload button in there, and I can gather some information that way, but I feel it is not completely accurate for startup since the reload button also seems to trigger the "install app" flow and the "app installed" popup. It also appears like the app window is not completely destroyed and started fresh each time. James [1] https://groups.google.com/forum/#!topic/mozilla.dev.platform/F3Mp6dZonMA [2] https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Profiling_with_the_Built-in_Profiler#Other_Ways_to_Profile_B2G [3] https://github.com/jrburke/fxos-startup-test _______________________________________________ dev-b2g mailing list [email protected] https://lists.mozilla.org/listinfo/dev-b2g
