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Does anyone else find this article, while interesting, a little odd? In that I'm not sure that his argument succeeds. Especially in that while he portends to sh

Does anyone else find this article, while interesting, a little odd? In that I'm not sure that his argument succeeds. Especially in that while he portends to show that "there is no such thing as a general purpose processor", the first line of his conclusion starts "The general purpose processors of today.." It reminds me a little of philosophical arguments which attempt to disprove the existence of something common-sensical. If you define a general purpose processor as one which would be able to execute any algorithm comparably performant as a purpose-defined processor, then yes, that processor does not exist. But that's like saying processors with infinite cores, speed, and heat-dissipation capacity don't exist. It's true, but not all that interesting. "General purpose processors don't exist" is certainly an eyeball grabbing headline, but I think his "real" conclusion is more measured and in a way less controversial: "Efficient designs will require admitting that there is no one-size-fits-all processor design and that there is a large spectrum, with different trade-offs at different points." Despite his not defining "efficiency", that point seems true, but not that controversial. Does he show that "General-purpose processor" is not a useful distinction? I don't think so. (Apologies: recovering philosopher, not a CS PhD.)

Chinjut 12y ago
I think the point is that what we think of as an archetypal "general-purpose processor" is a somewhat arbitrary point in the space of possible architectures, and to think of other designs as in some sense secondary simply for failure to match this particular model is to lose sight of the true scope of general computation. Is it uncontroversial? Perhaps no one would disagree after hearing it spelt out, but I think it certainly is the case that people often naively think of "general-purpose processor" in just the way the author worries about, and that reading something like this can bring about a helpful shift in perspective.
- kazinator 12y ago
  That would be an argument against someone who claims that the general purpose processor, to be general purpose, has to look like those familiar ones which we have. Put another way: a particular point in a large space of "general purpose" doesn't indicate special purpose. You have to choose a point to implement something.
scott_s 12y ago
I had a similar reaction. I knew the point he was making, but I didn't like the way he has making it. I think that if he came right out and said his point - articulated succinctly by Chinjut in a sibling comment - it would be a more effective essay. Dispense with the cute semantic quibbling, and present your real point.

Chinjut 12y ago

I think the point is that what we think of as an archetypal "general-purpose processor" is a somewhat arbitrary point in the space of possible architectures, and to think of other designs as in some sense secondary simply for failure to match this particular model is to lose sight of the true scope of general computation. Is it uncontroversial? Perhaps no one would disagree after hearing it spelt out, but I think it certainly is the case that people often naively think of "general-purpose processor" in just the way the author worries about, and that reading something like this can bring about a helpful shift in perspective.

kazinator 12y ago
That would be an argument against someone who claims that the general purpose processor, to be general purpose, has to look like those familiar ones which we have. Put another way: a particular point in a large space of "general purpose" doesn't indicate special purpose. You have to choose a point to implement something.

scott_s 12y ago

I had a similar reaction. I knew the point he was making, but I didn't like the way he has making it. I think that if he came right out and said his point - articulated succinctly by Chinjut in a sibling comment - it would be a more effective essay. Dispense with the cute semantic quibbling, and present your real point.