android heapStartSize heapMaximumSize heapGrowthLimit heapSize说明

尊重原创作者，转载请注明出处：

http://blog.csdn.net/gemmem/article/details/12008005

dalvik/vm/Globals.java代码片段：

struct DvmGlobals {
/*
* Some options from the command line or environment.
*/
char* bootClassPathStr;
char* classPathStr;


size_t heapStartingSize;
size_t heapMaximumSize;
size_t heapGrowthLimit;
size_t stackSize;
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heapStartingSize是进程启动时java heap的初始大小

heapMaximumSize的值必须大于heapGrowthLimit，当heapGrowthLimit值为0时，heapGrowthLimit就被赋值为heapMaximumSize。当Java堆对象总和达到heapGrowthLimit时，dalvik会抛出Error级别的异常，java app的主线程的DefaultUncaughtExceptionHandler会执行，弹出对话框提示app结束。

代码如下：dalvik/vm/alloc/Heap.cpp

/*
* Initialize the GC heap.
*
* Returns true if successful, false otherwise.
*/
bool dvmHeapStartup()
{
GcHeap *gcHeap;


if (gDvm.heapGrowthLimit == 0) {
gDvm.heapGrowthLimit = gDvm.heapMaximumSize;
}


gcHeap = dvmHeapSourceStartup(gDvm.heapStartingSize,
gDvm.heapMaximumSize,
gDvm.heapGrowthLimit);
if (gcHeap == NULL) {
return false;
}

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dalvik.vm.heapsize这个property只对largeHeap的app起作用。当app的AndroidManifest.xml设置了大内存，heapGrowthLimit就不起作用了。