qmlscene often has significant slowdown, eating up the CPU

[Jono Bacon]

I have been seeing consistent slowdowns happening every so often, and recently I noticed it with the terminal app running, so I ran top and 'qmlscene' was taking up 99% of the CPU. These slowdowns seem pretty random, so I am not sure of the cause, but it seems qmlscene may be where the slowdown occurs.

[Olli Ries (ories)]

Saviq, can we enable any extra logging by default to catch more data for such situations?

[kevin gunn (kgunn72)]

reassigning...this sounds a lot like https://launchpad.net/bugs/1234906
feel free to dup if you feel it is

[Michael Zanetti (mzanetti)]

@Olli: We do have logging in ~/.cache/upstart/unity8.log which currently is the catch all logfile. I don't think we can enabling anything more than what the app is printing itself (which will end up in unity8.log)

@Jono: Please attach ~/.cache/ustart/unity8.log. Also, please note down which applications show this issue and if possible steps to trigger this issue.

@Kevin: No... I don't think those bugs have anything in common.

Also, Unity8 is most likely the wrong component for this bug. As qmlscene spinning the CPU indicates most likely a bug in an application. There is a chance that the QPA plugin is causing this but somewhat unlikely as we probably would see it waaay more often.

[Launchpad Janitor (janitor)]

[Expired for unity8 (Ubuntu) because there has been no activity for 60 days.]