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Intel Pushes Pentium 4 Past 3 GHz
denisbergeron writes "Yahoo has the news about the new P4 who will run at nothing less than 3.06 GHz. But the great avance will be the hyperthreading technology (already present in Xeon) that allows multiple software threads to run more efficiently on a single processor."
Hyperthreading is a complex proof of the limitations of todays CPU architectures. I belive in a CPU architecture containing many small CPU cores on one chip, instead of just multiplying the issue and commit parts and sharing the execution units.
It would be more scaleable and easier to implement to use several complete CPUs. The biggest drawback (compared to hyperthreading) would of course be that in special situations some CPU cores would be idle, but this simply corresponds to pipe-line bubbles in the hyperthreaded case. This is easily compensated by two facts: 1) multiple CPUs can be made very scalable and 2) most computer systems today always runs multiple threads (i.e. utilization will be good).
Of course, for Intel to maintain their market lead, everything has to be compatible, so they'll have to pay, time after time, for the errors they made in the eighties (the 286 paging + the CISC ISA). By breaking Amdahl's law time after time (SSE, MMX, etc.) they have made an even more complex beast. The only area where they really excel is in the production processing. They can squeeze out high frequencies and pack the transistors tight. For that, I'll give 'em cred. For their CPU ISAs, I'll just laugh...
Maybe you don't want 3.06 GHz for what you're working on, but our "Enterprise Class Systems" (Win2k application servers) can use all the CPU we can throw at them. Everyone has different needs, and for a lot of folks, faster processors are a good thing.
Are they actually CPU bound, or are they slowed by memory access and bus bandwidth? Apart from certain numerical computations, I have rarely seen cases in which the CPU is really fully occupied, altho' the tools often report that it is. For example, tools will report if the CPU is idle waiting for a page fault to the swapfile, but not if it's waiting for data to get to or from main memory, it just looks like the CPU is occupied.
Knowing what I know of Citrix, it alone is far bigger than the L2, and that's before even considering the user applications. It requires the CPU to switch context heavily, and constantly flush and reload its L1/2/3 caches. After all, if you need 4G of RAM to run the applications you are using, and you have say an 8M cache, the CPU is going to be spending a lot of time managing its cache rather than doing useful work. Given that, it is bound by memory access, not raw CPU.
Manufacturers, driving by consumer marketing which believes that higher Mhz == better product, are optimizing in the wrong areas. If they want to talk numbers, they should be pushing fast memory and buses which are actually a useful measure of a machine's performance, not CPU Mhz which isn't.
Why not spend more R&D money in increasing the speed of the bus? It would give us way better performance.
Whoopie. Another EE student who has realized that the paper design of the PC architecture sucks wind and can't imagine that it works at all.
Don't worry folks. In a few years he'll graduate and get some real world experience. And then he'll probably realize that while the PC architecture does indeed suck on paper, in reality it's not all that bad. Could it be better? Sure. Should we throw the baby out with the bathwater? No way.
Compare the PC market to the rest of the computer market. Who's made more progress? Who has been rapidly pushing the niche markets into smaller and smaller niches as their "superior designs" find them running slower and more costly than the evil, horribly misdesigned PCs?
Coprocessors? Yeah... have you even bothered to look at a modern video card recently? The damn things are more complex and more powerful than the CPU. Modern audio boards are also powerful all by themselves. For the most part I/O is handled by separate chips as well.
The bus and memory interfaces on PCs could use some work. And that's happening, with 3GIO, PCI-X, and other buses being implemented in the next few years. There's some truely horrid cruft in the core too - the IRQs, DMA channels, etc. are still pretty godawful, but not nearly as godawful as they were back with the ISA bus. The issues haven't so much gone away as they've been hidden, but the performance limitations imposed really aren't all that absurd.
Design a better machine? Go for it. It'll die just like all the rest because while you may have a better electrical design, you've ignored the real world and the fact that people want to be able to make slow transitions from one architecture to another. Doing an all-at-once transition is not an option unless you control the entire market - which no PC manufacturer does (unlike Apple). Of course, the flip side of this is that the competition causes the current implementation to advance far more rapidly than would be otherwise possible. Which is why you can buy a $2000 PC that outperforms a $200,000 server.
The true fact in the matter is that intel are going to rely almost entirely on the marketability of a big number with the P4, as it's handling is rather unimpressive when compared to such ordinary designs as those from AMD, which clock poorly, yet crunch happily.
I need not mention about G4's and other well designed chips as some GHz bunny is certain to point out that they are only at 1.25GHz at the moment.
I know that there are some of you on here that will flame me saying that you DO use that power. And that's fine, you are the 1% of the population I mentioned earlier.
Everyone, of course, believes they're in that 1%.
I used to do commercial 3D video game development on a 450MHz P2. It was a bit slow when compiling, but acceptable otherwise. Then I upgraded to an 866MHz P3 and, even years later, it still feels like lightning. Compiles are quick. Everything is snappy. I've taken to writing tools in Perl and Lisp and Python, and they're snappy as well. I mean, geez, who would have thought ten years ago thay you'd ever be able write 3D geometry manipulation tools in Lisp and have no worries about performance?
Now, of course, you can buy a 2.5GHz P4 in an $800 PC. This is beyond ridiculous. Everything is three times faster than "beyond the point of caring"? I'm going to put C++ aside for almost everything, and just use whatever is the most abstract. Haskell? Yes, please.
Am I in the 1%? Certainly not.
It may help the economy in the short term, but you will just be wasting precious electricity (in this case gobs of it) just to say you have the latest and greatest. It's becoming a disease!
This bothers me, too. Yeah, people don't need all this performance, and that's okay. Who cares if your computer is too fast? But unfortunately you don't get all this performance for free. It's coming at the premature obsolescence of hardware and greatly increased power consumption. Hard drives and monitors are actually improving in this regard, especially with LCD monitors (awesome!). But now we have 70 watt processors and PCs that ship with five or more fans in them, and we're talking bottom end machines from Dell and Gateway here, not crazy high-end monsters. This is bad.