Lucata Pathfinder FAQs¶
This page details answers to some commonly asked questions about the Lucata Pathfinder system.
What are the detailed specs for GT’s Pathfinder systems?¶
GT currently hosts a four-chassis Pathfinder system which has 32 nodes in total with 8 in each chassis. The nodes are connected directly via RapidIO links.
- Stationary cores per node/chassis: 1/8
- Memory-side processors per node/chassis: 8/64
- Memory channel width: 16 bit
- Memory per node/chassis: 64 GB/512 GB
- Gossamer Cores or Lucata Compute Elements (LCE) per node/chassis: 24/192
- LCE clock speed: ~220 MHz (may be slightly higher/lower)
- Maximum number of concurrent threads per node/chassis: 1536/12,288 (additional spawned threads sit in the run queue)
- Power usage per chassis: ~2KW max although likely lower in practice
- System node CPUs are PowerPC e6500 T2080 CPUs with 8 cores, running at 1.8 GHz
- Nodes inside a chassis are connected to 6 internal switches that each have 12 ports
- 4 ports per switch can be used to connect to other chassis while other ports connect to all 8 nodes in an endpoint star formation
- Within a chassis each node should be accessible within 1 switch hop; 2 chassis requires 2 switch hops
- Note that GT does not have a rack-mounted switch that would further scale the network.