Why so many GC_FOR_ALLOC in a simple app?

user_3090786 0
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I'm getting way too many GC_FOR_ALLOC from the dalvikvm. I'm getting XML from a REST service: in one activity I parse about 100 lines programatically(me) and in the other activity I use the SimpleXML to parse about 200 lines.

In the first one I get 50 GC_FOR_ALLOC. In the second one I get like 300!! (I can't even post it all, the body makes 29579 characters and it's allowed only 30k)

I've searched and almost everyone complains about gc_for_"M"alloc and not gc_for_"A"lloc.

Is the SimpleXML the problem because the instances created?

I'll post the logcat dump by dalvikvm, maybe the values have some information.

Thank you very much for your help.

12-11 06:13:49.564: D/dalvikvm(6759): GC_FOR_ALLOC freed 362K, 13% free 4116K/4688K, paused 181ms, total 182ms
12-11 06:13:50.074: D/dalvikvm(6759): GC_FOR_ALLOC freed 303K, 13% free 4134K/4708K, paused 142ms, total 142ms
.... repeated many times .....
12-11 06:14:06.254: D/dalvikvm(6759): GC_FOR_ALLOC freed 73K, 13% free 4159K/4768K, paused 53ms, total 53ms
12-11 06:14:06.314: D/dalvikvm(6759): GC_FOR_ALLOC freed 103K, 13% free 4159K/4768K, paused 56ms, total 57ms
12-11 06:14:06.374: D/dalvikvm(6759): GC_FOR_ALLOC freed 29K, 12% free 4203K/4768K, paused 54ms, total 54ms
12-11 06:14:06.424: D/dalvikvm(6759): GC_FOR_ALLOC freed 73K, 13% fre
dalvik android performance
6 Answers

My log:

D/dalvikvm: GC_FOR_ALLOC freed 549K, 9% free 7878K/8596K, paused 30ms, total 34ms

...freed 539K, 9% free 7888K/8596K, paused 30ms, total 30ms
...freed 1856K, 21% free 8083K/10108K, paused 51ms, total 51ms
...freed 582K, 9% free 7845K/8596K, paused 38ms, total 38ms

Explain:

When your app get memory more limit per app. Dalvik/Ant call garbage collector.

What limits memory for your App decide Dalvik/Ant. As you see for my app Dalvik decide 8596K(double case) and 8083K(one case).

And limits change in runtime.

And you can not be sure when this happens. But you can reduce the likelihood. Decreasing the amount of memory that your application consumes.

PS: Decide when call GC teakes Dalvik/Ant. And you can not be sure when this happens. But you can reduce the likelihood. Decreasing the amount of memory that your application consumes.

PS: In "Monitor android" see tab "Monitors", graphics "Memory". And use buttons: "pause(enabled)", Initiate GC, "Dump Java Heap" "Start Alocation Tracking(very useful)". And use official guide for this:

https://developer.android.com/studio/profile/am-memory.html?utm_source=android-studio.

As far as I understand App must not stop/pause working or crashes when VM call GC.

user_45924480
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