public static void logAddToList(int arenaIx, int headerIx, int listIx, int listHead) {
      if (casLog == null) return;
      int ix = casLog.offset.addAndGet(4) - 4;
      casLog.log[ix] = makeIntPair(ADD_TO_LIST, listIx);
      casLog.log[ix + 1] = Thread.currentThread().getId();
      casLog.log[ix + 2] = makeIntPair(arenaIx, headerIx);
      casLog.log[ix + 3] = listHead;
    }
Unsets the headers (meaning this does not refer to a buffer).
llap-server/src/java/org/apache/hadoop/hive/llap/cache/BuddyAllocator.java