Via El Reg:
Since the annoucement that IBM will sell off Opteron-server a couple of days ago there were only little details available; now IBM annouced some details and they’re quite juicy: Three Opteron-server models will have HTX-slots.
The whole HTX-concept is really cool: You can plugin accelerator-boards or co-processors directly into AMD’s Hyper Transport Bus which enables direct communication with the CPU and Memory without going through a Memory Controller Hub or Northbridge. The latency is much lower as traditional connection-technologies like PCI-X.
Cray uses a similar approach with their SeaStar communication chip on the XT3 supercomputer.
Their Opteron-based XD1 has a latency of 1.7 us in the same cabinet from CPU-to-CPU, 2.0 us to remote cabinets – done by Hyper Transport.
This is going to be an interesting summer; HTX is the best invention since sliced bread imho.