Multiple issues are at play: 1) the regression seemingly observed in http://reqorts.qa.ubuntu.com/reports/qa/performance/dashboard/index.html turned out to be only a temporary blip. Subsequent runs show that there was no recent change in camera app startup time (on krillin).
2) the startup time measurement done in http://reqorts.qa.ubuntu.com/ is tricked by the way the camera app does things: it starts as fast as possible but once started shows a black screen for several seconds. It turns out that from a user perspective the camera app does not take 2.5s to startup on krillin but closer to 4.5s. Stopwatch measurements are as follows: - krillin (363): 4.5s - arale (356): 5s - turbo (110): 7s 3) on turbo and I suspect some other devices or some other circumstances, the camera app startup is exceedingly high (over 7s) which I believe explains the reports we are getting here. After studying it I could not yet pinpoint the exact cause for such a slowdown. However I noticed that launching the camera app from the SDK made it start considerably faster, in 3s instead of 7s. After digging I came up with a small script that reproduces that speedup: http://pastebin.ubuntu.com/17696727/ Finally, I realised that simply having a "tail -f /var/log/syslog" opened while starting the camera app was enough to do the trick. I investigated the possibility of CPU cores not being online in normal camera app startup thus possibly slowing it down but manually turning them on did not improve situation. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1592447 Title: camera startup time regression To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1592447/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
