public RawPageSpace(String name, int pageBudget, int mb) { super(name, false, false, mb);
public RawPageSpace(String name, int pageBudget, Address start, Extent bytes) { super(name, false, false, start, bytes);
  public RawPageSpace(String name, int pageBudget, int mb) {    super(name, false, false, mb);    pr = new FreeListPageResource(pageBudget, this, start, extent);  }