TestShrinkToOneRegion.java

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/*
 * @test TestShrinkToOneRegion.java
 * @bug 8013872
 * @requires vm.gc=="G1" | vm.gc=="null"
 * @summary Shrinking the heap down to one region used to hit an assert
 * @run main/othervm -XX:+UseG1GC -XX:G1HeapRegionSize=32m -Xmx256m TestShrinkToOneRegion
 *
 * Doing a System.gc() without having allocated many objects will shrink the heap.
 * With a large region size we will shrink the heap to one region.
 */
public class TestShrinkToOneRegion {
    public static void main(String[] args) {
        System.gc();
    }
}