How to reproduce Java OutOfMemoryError - GC overhead limit exceeded

Question

My approach was to create hundred thousand local collections and populate them with random strings, something like this:

    SecureRandom random = new Secure         


        

Answer 1

I think this should do the trick ... if you run it long enough:

HashMap map = new HashMap();
for (long i = 0; true; i++) {
    for (int j = 0; j < 100; j++) {
        String s = "" + j;
        map.put(i, s);
    }
}

What I'm doing is slowly building up the amount of the non-garbage, while creating a significant amount of garbage at the same time. If this is run until the non-garbage fills nearly all of the heap, the GC will get to a point where the % of time spent garbage collecting exceeds the threshold.