What do you call the "action of" striping threads across multiple processors?

-1

A question of curiousity,
I understand [one thread per core] or with time slicing, [many threads one core] But, is there a way even through emulation, even with a performance cost, to...
how to say... "have many processors think they are one processor"

Its possibly an elementary question, but if you could provide me with even a Keyword to search by so that i can learn more. That would be awesome.

Note: My hypothetical application would be running a process that doesnt require real-time operation, Like a single threaded video encoder, or compression utility.

TardisGuy

Posted 2012-12-12T01:25:55.253

Reputation: 436

I dont think it is possible, not usefully anyway.. – Karthik T – 2012-12-12T01:39:04.747

It's not really clear what you're asking. If they "think they are one processor", why aren't they? – David Schwartz – 2012-12-12T01:42:45.630

@DavidSchwartz I think he wants to, somehow, merge 4 processors(cores) into 1 and boost performance on serial applications – Karthik T – 2012-12-12T01:57:55.270

2I think you're attempting to describe "parallel processing", which is a major area of research. Basically either humans or specialized compilers need to "parallelize" the application software so that parts of it can execute on different processors. A non-trivial task. – Daniel R Hicks – 2012-12-12T02:24:27.827

Well, n processors will “think they are one processor” if n – 1 of them are turned off. I don’t want to be flippant; I want to point out that I don’t understand your question, and I suspect that nobody else here does either. Can you try to explain it better? – Scott – 2012-12-12T02:39:42.823

Answers

Maybe what you are thinking of is automatic parallelization. This process happens at a software level, though, in compilers, not at a hardware level. A parallelizing compiler takes single-threaded code and tries to transform it into multithreaded code, which can then run in parallel on multiple processors. I get the impression that this sort of thing is still at a research stage, though, and is not commonly used in the real world.

dangph

Posted 2012-12-12T01:25:55.253

Reputation: 3 478

If there was a way to do this, we'd have processors with fewer cores. The reason we've gone to multi-core processors is that we don't know how to make cores any faster than they already are.

David Schwartz

Posted 2012-12-12T01:25:55.253

Reputation: 58 310

Actually, if there was a sufficiently general and effective way to do this we'd have processors with far more cores. – Daniel R Hicks – 2012-12-12T02:25:26.223

@DanielRHicks: No. If there was any known way to make one super-fast core, that's what we'd have. Its internal details would be totally invisible from the outside. – David Schwartz – 2012-12-12T02:27:20.593

The point is that it's easy to make multiple cores, but putting them to use is the problem. If "parallelizing" a program were simple then massively parallel laptops would be the norm. But four cores is about the most that a "personal" computer can effectively use. – Daniel R Hicks – 2012-12-13T01:11:24.687