Read this carefully.
http://download.oracle.com/javase/7/docs/platform/jvmti/jvmti.html#VMObjectAlloc
-kto
On Jun 10, 2011, at 11:28 AM, Keith McGuigan wrote:
>
> Forwarding to serviceability-dev (and Bcc'ing hotspot-runtime-dev off).
>
> I personally don't see anything obviously wrong in the code you sent but it
> looks like you've only sent a small fragment of the code and the problem
> could well be somewhere else. What is the output, and what do you expect?
> Does it count 6, 600, or 6000, 60000 or what? Is it even close? What
> happens when you change the number of iterations in the java program? Are
> you seeing any other threads calling allocation, and if so are you
> implementing the proper locking for your gdata?
>
> --
> - Keith
>
> On Jun 10, 2011, at 1:58 PM, Lee Ming wrote:
>
>> Hi,
>> I'm doing some test with JVMTI VMObjectAlloc, and it seems like the callback
>> cant catch object allocation properly .e.g: regardless how I tried to
>> allocate new objects in Java program, the agent still report the same number
>> of objects allocated.
>>
>> This is the source code of the callback
>>
>> char *generic_name;
>> jvmtiThreadInfo info;
>> jvmtiError error;
>>
>> (void)memset(&info, 0, sizeof(info));
>>
>> error = (*jvmti)->GetClassSignature(jvmti,
>> object_klass,&generic_name,NULL);
>> check_jvmti_error(jvmti, error, "can't get class name");
>> //printf(generic_name);
>>
>> gdata->object_size = gdata->object_size + size;
>> gdata->ccount++;
>>
>> stdout_message("%d.Object allocated, class:
>> %s\tsize:%d\n",gdata->ccount,gener! ic_name,size);
>> printf("total size now is: %I64d\n",gdata->object_size);
>>
>>
>> error = (*jvmti)->GetThreadInfo(jvmti,thread, &info);
>> check_jvmti_error(jvmti, error, "can't get thread info");
>> printf("thread name:%s\n",info.name);
>> (*jvmti)->Deallocate(jvmti, (unsigned char *) info.name);
>> (*env)->DeleteLocalRef(env, info.thread_group);
>> (*env)->DeleteLocalRef(env, info.context_class_loader);
>>
>> And the sample Java test file
>> public class Test {
>>
>> public static void main(String[] args){
>>
>> for(int i=0; i<10000;i++){
>> &nbs! p; &n bsp; Hello h1 = new Hello(1,2);
>> Hello h2 = new Hello(3,4444);
>> Hello h3 = new Hello(3,44);
>> h1.w();
>> h2.w();
>> h3.w();
>> //System.ou! t.println("alloc");
>> }
>>
>> }
>>
>> }
>>
>> Please let's me know whether i have made any mistake
>>
>> Thank you
>> Bhm
>
