Origin2000
Origin2000 is a massively parallel computer from Silicon Graphics (SGI) that was introduced in 1996. It is a ccNUMA system with distributed, shared memory ( Distributed Shared Memory DSM) up to 512 at the MIPS R10000-, R12000- or R14000- processors with up to 600 MHz over NUMAlink be coupled to said high-speed connections.
NUMAlink connection network
The processors of an Origin2000 are connected in pairs to a crossbar switch called a hub . These hubs are connected to one another via a network of NUMAlinks , which form a hypercube and have routers at their nodes . Since the router chips only have six NUMAlink connections, a fat hypercube topology must be used for 64 or more processors . The NUMAlinks transport 1.6 gigabytes bidirectionally . At the beginning, the name CrayLink was used instead of NUMAlink to refer to the 1996 takeover of Cray Research. Cray technology was only used in the next NUMAlink generation.
XIO input / output system
In addition to NUMAlink and memory, the hubs also connect the processors to the XBow - input / output crossbar switches to which a total of eight input / output or processor cards can be connected. The XIO connection used is electrically identical to the NUMAlinks, but the protocol is optimized for input / output and cannot be routed. Like the NUMAlinks, XIO transfers 1.6 GB bidirectionally, ie an XIO card can transfer data to the Origin2000 at 800 MB / s.
Mechanical construction
Each Origin2000 consists of one or more compute modules , two of which are installed in a 19-inch cabinet. Each compute module accommodates one to four processor boards with two processors each and up to four gigabytes of memory. Two XBow input / output crossbars are mounted on the backplane of the modules, which allow the connection of up to 12 XIO cards. A card called BaseIO is installed as standard and provides a console connection, network and mass storage connection ( SCSI ). A PCI card cage can be inserted into an extra- wide XIO slot , which allows the installation of up to three PCI66-64 cards.
Furthermore, two router boards can be used in each computer module in order to connect it to other computer modules via NUMAlink. Each module can with two CD-ROM - and / or DAT -Laufwerken and up to six SCSI / SCA - hard drives can be fitted.
In the expansion with more than 64 processors, another meta router cabinet must be added to the cabinets with computer modules in order to implement the expansion to the fat hypercube topology. Thus, an Origin2000 in the maximum configuration with 512 processors comprises 33 19-inch cabinets.
Graphics extension for Onyx2
An Origin2000 can be expanded to an Onyx2 by adding one or more graphics modules , each with one or two InfiniteReality graphics pipes . In this combination, referred to by SGI as a graphics supercomputer , up to two graphics modules with two pipes can be connected to each compute module via XIO. This enables the construction of complex simulation and visualization applications .
programming
Like all NUMAlink systems from SGI, the Origin2000 is programmed like a normal SMP system, ie no special precautions are necessary to distribute the tasks to the processors or to communicate the processes. This is done automatically by the IRIX operating system in cooperation with the hardware . Only when you need the last 5% power do you have to optimize the software used for the ccNUMA system. However, programs written for cluster systems can also be easily ported via an adapted MPI implementation.