NUMAlink

As NUMAlink a high-speed network of Silicon Graphics (SGI ) is called, which serves to connect the compute nodes in the massively parallel computers of the ccNUMA Origin and Altix families.

The DASH prototype ( NUMAlink -1)

Early 90s was developed at Stanford University, the DASH ( Directory Architecture for Shared Memory ) prototype to test the viability of the concept of the ccNUMA architecture. The DASH uses two separate, parallel run, 16 -bit-wide networks (one for requests and one for responses). The networks form a rectangular grid, take over at the node router traffic control. On the router, the computing nodes are also connected. As computing nodes are used Powerstation 4D/340 SGI, the routers are plug-in cards discrete. The transfer rate is 120 MB / s with a latency of 50 nanoseconds per "hop". The term " NUMAlink -1" is not official, but since the next generation is termed NUMAlink -2, the allocation is warranted.

NUMAlink -2 aka CrayLink

The first public appearance of NUMAlink took place in 1996 with the introduction of the SGI Origin2000 through instead. Since SGI had just taken over Cray Research was used for marketing reasons, the name " CrayLink ", although not a Cray technology was used. After Cray Research was sold to Tera Computer in 2000, the name NUMAlink has been introduced. For NUMAlink - 2, the two separate networks have been integrated, a common connection, and the speed is (significantly) increased to 800 MB / s, with full-duplex, and is transmitted as an aggregate bandwidth of 1.6 GB / s is achieved. As a hypercube topology was chosen in order to achieve with a limited number of cable all nodes within a few hops can. In this case, this topology also ensures an excellent bisection bandwidth. The router has been integrated on a chip, which provides six ports. For 32 nodes, all six ports are occupied and it needs to be gone over to Fat hypercube topology can be used in the addition metarouter.

NUMAlink -3 - Double Speed

The third NUMAlink generation was introduced in 2003 with the Origin 3000 and brings the most important innovation doubling the transfer rate to 1.6 or 3.2 gigabytes / s Accordingly, a new router chip would have to be designed only has eight router ports and as a simpler topology - Dual Plane Tree Fat - possible.

NUMAlink -4 - Quad Speed

For use in the new Altix family of Intel Itanium -based computers was with NUMAlink -4 again doubles the speed, now on 3.2 or 6.4 gigabytes / s Moreover NUMAlink -4 flexible with respect to the topology, next to Fat Tree is for example a ring as in the Altix 350 possible.