- ExascaleHPC Fabric Topology
Topologies –Fat Tree Example
Torus Topology
Mesh or 3DTorus
▪Mesh –each node is connected to 4 other nodes: positive and negative X and Y axis
▪3Dmesh –Each node is connected to 6 other nodes: positive and negative X, Y and Z axis
▪2D/3Dtorus –The ends of the 2D/3Dmeshes are connected
Dragonfly+ Topology
What is Dragonfly Topology?
Dragonfly is a hierarchical topology with the following properties:
Several “groups”, connected together using all to all links▪The topology inside each group can be any topology
▪Focus on reducing the number of long links and network diameter to reduce total cost of network
▪Requires Adaptive Routing to enable efficient operation
There are Different Dragonfly Topologies Options
Dragonfly+ Topology
▪Several “groups”, connected using all to all links
▪The topology inside each group can be any topology
▪Reduce total cost of network (fewer long cables)
▪Utilizes Adaptive Routing to for efficient operations ▪Simplifies future system expansion
Future Expansion of Dragonfly+ Based System
▪Dragonfly+ is the only topology that allows system expansion at zero cost
▪While maintaining bisection bandwidth
▪No port reservation
▪No re-cabling
Dragonfly+ Simplifies Scale Deployment and Cost
http://www.hpcadvisorycouncil.com/events/2019/APAC-AI-HPC/uploads/2018/07/Exascale-HPC-Fabric-Topology.pdf
