AMD working on reverse Hyper-Threading?
The folks at X86-secret.com (in French, translate here) claim to have received
word from an AMD engineer about some of the company's plans for its
post-K8 CPU architecture. Reportedly, AMD has a hardware threading
implementation in the works, which would work as a "reverse
Hyper-Threading" of sorts. Whereas Intel's Hyper-Threading allows
Netburst-based processors to emulate two CPU cores on a single physical processor, AMD's technology
would allow multiple physical CPU cores to emulate a single logical processor. This approach could make sense because increasing numbers of physical cores in future CPUs may offer diminishing gains as software becomes harder to parallelize efficiently. X86-secret says Intel is
working on a similar implementation, too, and that it has "presented its
vision for hardware threading many times over." We've seen one such research project from Intel involving speculative thread execution, but that technology involves new compilers as well as hardware-level support.