Eric (eric.kjellen.delete@this.gmail.com) on July 27, 2012 12:51 pm wrote:
> hobold (hobold.delete@this.vectorizer.org) on July 27, 2012 11:53 am
> wrote:
[...]
> > Do not rely
> CPUs maintaining the extent of this relative advantage over
> > GPUs. GPUs
> can still harvest a few fruits that aren't exactly low hanging, but
> > well
> in reach. CPUs have a hard time even only touching more fruit with merely
> >
> the tips of their outstretched metaphorical fingers.
> >
> >
>
> But
> wouldn't that decrease their advantage in compute efficiency in a rather linear
> fashion? I.e. CPU and GPU architectures would converge and make it a straight-up
> race of process technology, memory bandwidth, cache latency, brand predictor
> quality etc. I don't see AMD or Nvidia winning that kind of contest in the long
> run either.

In the limit, convergence would be perfect, and everyone would have more or less the same product. For that reason, I don't dare to predict a winner either.

What I am trying to say is that the race can go on for quite a while yet. CPUs will focus more on improving or at least maintaining good single thread performance for spaghetti code, and GPUs will focus more on increasing or at least maintaining a throughput advantage. Each will still try to invade into the other's markets, but has to be careful not to give up their traditional lead (and lose the corresponding customers).

The tendency for convergence is strong, perhaps irresistible. But I think some repelling force will emerge as both try to maintain their historical advantage over the other. In some sense, the integration of on-chip GPUs into CPUs on the one hand, and Nvidia's diversification into ARM-SOCs on the other hand, is the result of both sides trying to avoid convergence. Instead, they mate two well differentiated types of processor on a single integrated piece of silicon.

Of course, there is also Larrabee ... but it has morphed into something that is no longer expected to excel at neither a CPU's nor a GPU's strengths. It looks like convergence cannot be rushed along this particular shortcut. At least not yet.