Hello, Replying to myself on this thread to give some news on this side.
Le 30/07/2015 12:41, Alexandre Lissy a écrit : [...] > > There's another big issue: the |observe()| method does a > |mozSettings.addObserver()| each times it is called. > > Code using this should be aware of this. We landed "unobserve" method to > make it more obvious that this needs to be taken care of. > > Now, one issue that is specific to System app mostly is the case where > code path that does |SettingsListener.observe()| are called in a > recurrent manner. This is leaking observers on the API. > > As much as I debugged last time on the API side, it was quite tricky to > detect those bad cases. We do cleanup observers reference when > windows/apps are being killed but System app is not always in this case. > > One nasty consequence of those leaks is that your device will slowly > become slower over time. > That is not something purely theoretical, we have a history of having some of those: - https://bugzilla.mozilla.org/show_bug.cgi?id=1089619 - https://bugzilla.mozilla.org/show_bug.cgi?id=1105639 - https://bugzilla.mozilla.org/show_bug.cgi?id=1189078 - https://bugzilla.mozilla.org/show_bug.cgi?id=1189758 - https://bugzilla.mozilla.org/show_bug.cgi?id=1193051 To help avoid letting those happen, we landed a change to the mozSettings API: https://bugzilla.mozilla.org/show_bug.cgi?id=1193469 Basically, we are: - lowering the threshold for number of observers that a SettingsManager instance can have on the same key from 20 to 10 - if we reach this threshold we will dump warning in the console - on debug builds this will throw We hope this will help people be able to more easily detect when there is such kind of leak happening. _______________________________________________ dev-b2g mailing list dev-b2g@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-b2g
