private boolean updateBufferedOperation(int index, Operation op ) {
		if(bufferedOperation.containsKey(index) ) {
			Operation alreadyWaitOp = bufferedOperation.get(index);
			if(transactions.get(alreadyWaitOp.getRWinfo().get(0)).isOlder(transactions.get(op.getRWinfo().get(0)))) {
				// transaction waiting for the var is older than that acquire to wait, so do not update buffer, abort op
				return false;
			}
			else {
				bufferedOperation.put(index, op);
				return true;
			}
		}
		else {
			bufferedOperation.put(index, op);
			return true;
		}
	}