Most of previous studies have assessed the performance issues for regular buffer and virtual channel organiza-tions and have not considered overall buffer size constraint. In this paper, the performance of mesh-based interconnection networks (mesh, torus and hypercube networks) under different traffic patterns (uniform, hotspot, and matrix-transpose) is studied. We investigate the effect of the number of virtual channels and their buffer lengths, on the performance of these topologies when the total buffer size associated to each physical channel (and thus router buffer size) is fixed. The results show that the optimal number of virtual channels and buffer length highly depends on the traffic pattern assumed.