By increasing the amount of resources on reconfigurable platforms with the abililty of partial reconfigurability, the issues of the management of these resources and their sharing among different tasks will become more of a concern. Online placement is one of these management issues that is investigated in this paper. Here we present a new approach for online placement of modules on reconfigurable devices, by managing the occupied space rather the free space on the device. Also an optimization of communication between running modules themselves and outside of the chip is proposed. The experimental results show a considerable decrease in communication and routing costs.