The Cray X1
is a non-uniform memory access
, vector processor supercomputer
manufactured and sold by Cray Inc.
. The X1 is often described as the unification of the Cray T90
, Cray SV1
, and Cray T3E
architectures into a single machine. The X1 shares the multistreaming processors, vector caches, and CMOS
design of the SV1, the highly scalable distributed memory design of the T3E, and the high memory bandwidth
and liquid cooling of the T90.
The X1 uses 1.2 ns (800 MHz) clock cycle, and 8-wide vector pipes in MSP mode, offering a peak speed of 12.8 gigaflops
per processor. Air-cooled models are available with up to 64 processors. Liquid-cooled systems scale to a theoretical maximum of 4096 processors, comprising 1024 shared-memory nodes
connected in a two-dimensional torus
network, in 32 frames. Such a system would supply a peak speed of 50 teraflops
. The largest unclassified X1 system was the 512 processor system at Oak Ridge National Laboratory
, though this has since been upgraded to an X1E system.
The X1 can be programmed either with widely-used message passing software like MPI
, or with shared-memory languages like Unified Parallel C
programming language or Co-array Fortran
. The X1 runs an operating system
which shares more with the SGI IRIX
operating system than it does with the UNICOS
found on prior generation Cray machines.
, Cray released the X1E
upgrade, which uses dual-core processors, allowing two quad-processor nodes to... Read More