OutOfMemoryError (on GCOverheadLimit)

[Florian Binder]

Hi Everyone,

I have seen an OutOfMemoryError can be thrown even if there would be 
enough space for the allocation (if it takes more than 98% of time or 
something like this).

But the javadoc of OutOfMemoryError says:
"Thrown when the Java Virtual Machine cannot allocate an object because 
it is out of memory, and no more memory could be made available by the 
garbage collector."

Therefore I thought an OutOfMemoryError can only be thrown if memory is 
allocated.

For the serial and parallel gc this is no problem, because the gc is 
only triggered on object allocations. But what is with the CMS or G1? 
When do they throw the OOME if the OverheadLimit is reached? On the next 
object allocation or immidiately (interrupting the thread[s] at any 
position)? And which Thread is getting the OOME? Only one, or all?

The reason for these questions is that I would like to know if OOME can 
be thrown only on object allocation or anytime.

Is it possible that the following method throws an OOME?:
public int  sumAll(int[] data) {
int sum = 0;
for(int i = 0; i < data.length; i++) {
sum += data[i];
}
return sum;
}

Thanks,
Flo