public void copyMemory(Object o1, long addr1, Object o2, long addr2, long size) {
    unsafe.copyMemory(o1, addr1, o2, addr2, size);
  }
Returns 4 if this is a 32bit jvm; otherwise 8. Note it does not account for compressed oops.
geode-unsafe/src/main/java/org/apache/geode/unsafe/internal/sun/misc/Unsafe.java