//public int GetMachinesCount()
        //{
        //    lock (_lock)
        //    {
        //        return MachineTable.GetMachinesCount();
        //    }
        //}

        public void PowerOffHost(int machineId)
        {
            lock (_lock)
            {
                var machine = MachineTable.GetMachineById(machineId);
                if ((machine as HostMachine).GetContainersCount() != 0)
                {
                    //return false;
                    throw new NotImplementedException();
                }
                else
                {
                    machine.StopMachine();
                    //PoweredOffMachinesTable.AddMachine(machine.MachineId, machine);
                    MachineTable.RemoveMachine(machineId);
                    DataHolder.RemoveUtilization(machineId);
                    ReadyMachineTable.AddMachine(machineId, machine);
                    //Console.WriteLine($"( ) Power off Host #{machineId}");

                    //return true;
                }
            }
        }