Hyperthreading?

[teamalpha]

what exactly does hyperthreading do?

[tgalati4]

It's a smoke and mirrors campaign by Intel. Do a wiki search on ViiV for a similar marketing campaign.

Basically, one processor has an instruction set that appears to be a dual processor--handling two threads simultaneously. How this is done is proprietary, but a google search will show you a few papers (by Intel) on the "benefits" of such an architecture.

Oh, I forgot. HT costs more.

[Lster]

Wikipedia has the answer:

http://en.wikipedia.org/wiki/Hyper_threading

If that isn't enough, consider asking a more specific question...

[cogadh]

what exactly does hyperthreading do?

Simple answer; it emulates the presence of two processors when there is actually only one.

[teamalpha]

They dont use it anymore then? (on dual/quad cores)

[omega_user]

Well, wouldn't hyperthreading be doubly helpful if say, you ran a dual core. 4x the power (by having designated processing branches). It seems hyper threading is just mimicking the way a GPU works, by having simultaneous processes, but only on the scale that a CPU does it (with more complexity)

[xelapond]

I don't think it would be very similar to GPUs because they run MIM D, wheras multi core processors(CPU) run at SIM D.

[omega_user]

I don't think it would be very similar to GPUs because they run MIM D, wheras multi core processors(CPU) run at SIM D.

Oh, no. I just meant at a basic level, instead of processing one at a time, the hyperthreading is doing multiple. I didn't mean the whole unit was acting just like a GPU

[xelapond]

Oh, sorry for the confusion:^) Yeah, I guess it kinda does, 'cept the GPU has the actual hardware and the CPU is emulating it.

Seams kind of a weird concept, emulate another core? I wonder how they got that to work...

[mikedep333]

A hyperthreaded CPU is something like 10% faster than a non-HT CPU, assuming your application is sufficiently well multithreaded to take advantage of both logical CPUs. That is the simple practical difference that it has.