Russell said:
What are some examples of important and performance-limited
computation tasks that aren't run in parallel?
I.e., that run fastest on a one-processor Itanium or Opteron or
Xeon workstation...
On the other hand, who isn't drooling over these:
http://www.orionmulti.com/products/
Quoting the press release on Transmeta's web site:
"The specifications for Orion's DS-96 deskside Cluster Workstation
include 96 nodes with 300 Gflops peak performance (150 sustained),
up to 192 gigabytes of memory and up to 9.6 terabytes of storage.
It consumes less than 1500 watts and fits unobtrusively under a
desk. Orion's DT-12 desktop Cluster Workstation has 12 nodes with
36 Gflops peak performance (18 sustained), up to 24 gigabytes of
DDR SDRAM memory and up to 1 terabyte of internal disk storage.
The DT-12 consumes less than 220 watts and is scalable to 48 nodes
by stacking up to four systems.
"Orion's desktop model will be available in October 2004, and the
deskside model will be available during the latter part of Q4. For
more information about Orion Multisystems and its products, visit
www.orionmultisystems.com.
Have to wonder why all of those nodes are hooked together (inside
the box, presumably on the motherboard) with gigabit ethernet,
rather than something like the Horus chipset that's been spoken
about here recently, given that the processors have HyperChannel
interfaces. My guess is that it let them offload system software
development onto the open source cluster community, without having
to even do device drivers. I guess that the HyperChannel is for
peripherals, and doesn't do interprocessor cache coherency anyway.
Still, you'd think that they could have come up with something
lighter-weight than gigabit ethernet, switched or not.
R Clint Whaley and others have been playing with Atlas on Eficions
recently, too. Don't look to be too bad, although there seem to
be some code-vs-data cache pressure issues. Two flops/clock peak
(2GFlop at 1GHz) realizing between 90% and 60% of peak on various
atlas kernels.
Cheers,