Hyper-Threading

[sllewe]

I am studying CPUs in my class at school and my Certifaction book doesnt talk about hyper-threading. I have a pentium 4 running at 3.02 GHz and it has hyper-threading. I must say i do notice a improvment when running multiple programs. But what is hyperthreading?


Thanks much
Sean

 

[howard_hopkinso]

Take a look at this Sean.

CPU's have execution pipelines; basically an on-chip cache of instructions to execute. Often, to increase speed, CPU's will have multiple pipelines.

Some operations cause what's called a "pipeline stall" - the CPU has to wait for, say, a floating point operation or a memory read. the CPU COULD be doing other stuff.

Hyperthreading is something Intel cooked up to use those "stall slots" in the execution pipeline to run multiple threads while the CPU would otherwise be stalled.

Regards Howard

 

[sllewe]

wowser

Howard you might as well teach my Computer install class at school. Now that you mentioned pipelines, it made sense. b/c we were studing about the single pipeline featured on the 386 back in the day.

Thanks agian
Sean