IB single-plane topology¶
A complete M-Cell assembly consists of four compute racks. Each rack contains 4 x physical IRUs - Independent rack units. Using one dual socket node per one blade slot leads to 8 logical IRUs. Each rack contains 4 x 2 SGI ICE X IB Premium Blades.
The SGI ICE X IB Premium Blade provides the first level of interconnection via dual 36-port Mellanox FDR InfiniBand ASIC switch with connections as follows:
- 9 ports from each switch chip connect to the unified backplane, to connect the 18 compute node slots
- 3 ports on each chip provide connectivity between the chips
- 24 ports from each switch chip connect to the external bulkhead, for a total of 48
IB Single-Plane Topology - ICEX M-Cell¶
Each color in each physical IRU represents one dual-switch ASIC switch.
IB Single-Plane Topology - Accelerated Nodes¶
Each of the 3 inter-connected D racks are equivalent to one half of M-Cell rack. 18 x D rack with MIC accelerated nodes [r21-r38] are equivalent to 3 M-Cell racks as shown in a diagram 7D Enhanced Hypercube.
As shown in a diagram IB Topology
- Racks 21, 22, 23, 24, 25, 26 are equivalent to one M-Cell rack.
- Racks 27, 28, 29, 30, 31, 32 are equivalent to one M-Cell rack.
- Racks 33, 34, 35, 36, 37, 38 are equivalent to one M-Cell rack.