Application UI freezes with GC messages

Question

Hi I am having a trouble with my android app. When the data is being entered in the database , Database query for reading data is not working and it freezes the UI with the following Logcat message.

  12-24 12:01:56.261: I/art(16943): Explicit concurrent mark sweep GC freed 33437(1578KB)    AllocSpace objects, 0(0B) LOS objects, 39% free, 24MB/40MB, paused 724us total 84.428ms
 12-24 12:01:57.050: I/art(16943): Explicit concurrent mark sweep GC freed 13651(640KB) AllocSpace objects, 0(0B) LOS objects, 39% free, 24MB/40MB, paused 929us total 94.389ms
 12-24 12:01:57.708: I/art(16943): Explicit concurrent mark sweep GC freed 13625(637KB) AllocSpace objects, 0(0B) LOS objects, 39% free, 24MB/40MB, paused 3.232ms total 77.678ms
 12-24 12:01:58.472: I/art(16943): Explicit concurrent mark sweep GC freed 13652(638KB) AllocSpace objects, 0(0B) LOS objects, 39% free, 24MB/40MB, paused 960us total 83.427ms
 12-24 12:01:59.221: I/art(16943): Explicit concurrent mark sweep GC freed 13884(648KB) AllocSpace objects, 0(0B) LOS objects, 39% free, 24MB/40MB, paused 817us total 77.259ms
 12-24 12:01:59.949: I/art(16943): Explicit concurrent mark sweep GC freed 13929(652KB) AllocSpace objects, 0(0B) LOS objects, 38% free, 25MB/41MB, paused 1.483ms total 67.075ms
 12-24 12:02:00.657: I/art(16943): Explicit concurrent mark sweep GC freed 13901(649KB) AllocSpace objects, 0(0B) LOS objects, 38% free, 25MB/41MB, paused 1.158ms total 87.732ms

I am not able to understand why is this happening. Any help would be appreciated. Thanks!!

Answer 1

Surely you are doing job on the Main Thread (UI Thread). you HAVE to do this job on a background thread meanwhile showing a loading or never-ending animation to show the user you are working on something.

Otherwise this kind of messages of GC are normal and are not a problem, any normal app could throw this messages.

You get an ANR problem 10sec after the start of the app? if so, it's 100% that the problem, you are working on the ui thread.

Hope this helps.