Dalvik堆大小和堆基

Question

I wonder how can I determine the heap base address and heap size,

I would like to be able to dump my application heap,

Is there any way to do it ?

Plus when I am trying to read the process memory map via /proc/pid/maps, I don't see the [heap] section, why ?

Does the DVM allocate anonymous regions using mmap ?

If yes how can I track them ?

Answer 1

I wonder how can I determine the heap base address and heap size,

I would like to be able to dump my application heap,

Is there any way to do it ?

public static void logHeap() {
                Double allocated = new Double(Debug.getNativeHeapAllocatedSize())/new Double((1048576));
                Double available = new Double(Debug.getNativeHeapSize())/1048576.0;
                Double free = new Double(Debug.getNativeHeapFreeSize())/1048576.0;
                DecimalFormat df = new DecimalFormat();
                df.setMaximumFractionDigits(2);
                df.setMinimumFractionDigits(2);

                Log.d("tag", "debug. =================================");
                Log.d("tag", "debug.heap native: allocated " + df.format(allocated) + "MB of " + df.format(available) + "MB (" + df.format(free) + "MB free)");
                Log.d("tag", "debug.memory: allocated: " + df.format(new Double(Runtime.getRuntime().totalMemory()/1048576)) + "MB of " + df.format(new Double(Runtime.getRuntime().maxMemory()/1048576))+ "MB (" + df.format(new Double(Runtime.getRuntime().freeMemory()/1048576)) +"MB free)");
            }

Does the DVM allocate anonymous regions using mmap ?

If yes how can I track them ?

read https://source.android.com/devices/tech/dalvik/index.html

Answer 2

In linux API, you can use showmap to dump the heap size information, and the section is /ashmem/dalvik-heap . And the Android DDMS gives us two tools for analysis the Java heap and Native heap. Java Heap is Android Hprof, and the native heap is the native heap analysis.