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Cray XD1 Now Available

cyngus writes "Cray announced the availability of their XD1 systems. Each XD1 chassis has up to 12 AMD Operton processors. Up to 12 chassis can be clustered together in a rack. The XD1 uses Cray RapidArray Interconnect technology, based on HyperTransport, for high bandwidth and low latency communications between processors and chassises. The XD1 also has a handful of other technologies aimed at the HPC market, including Xilinx FPGAs, communications accelerators, etc."

2 of 200 comments (clear)

  1. Re:long time no news... by cyngus · · Score: 5, Interesting

    SGI does not own CRAY. They did buy them back in 1996. SGI sold its Cray unit in 2000 to Tera Computer.

  2. Hell, yeah! by DarkMan · · Score: 4, Interesting

    For my apps, I do iterative matrix calculations. However, one of the required data tables scales as n^2.3 (ish) of the system size. These can be precalculated, or calculated on demand. Typical size for a small run is 4-6 GB. I've filled a 40 GB array with data tables before.

    Thus, the part that impacts runtimes the most is either the on disc lookup, which is still faster than direct calculation, which we've also had to do.

    I looked into FPGA's a while back. Some back of envelope calculations show that a single FPGA should be able to calculated the data table on demand, and it'll be faster than reading from disc.

    (Turns out, that to actually get a usable solution for a basic PC would need to hack up the whole tool chain. FPGA cards for a PC are all designed for DSP, rather than numerics).

    So, with an FPGA and a CPU, I could elminated the slowest part of the job, and scale up to, what, a 1GB working matrix, which is about 8 time larger than the biggest job I've ever run, which hogged a T3E1200 for 6 hours.

    So, in short, gimme an FPGA and some reasonable tool chain, and I will be able to about half runtimes, and, more importantly, scale up to 10 times larger calculations. 5 time larger calculations is the most I've ever been asked about.

    Time to brush up on my VHDL, I think.