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What's Next in CPU Land after Itanium?
"I work for a major research organization. Of late a lot of the normal big computer companies have been visiting and preaching the gospel of
Itanium. My question to them, and to the assembled masses here at Slashdot is what happens next when Itanium is real? My world view is that Itanium based systems will become commodity products very quickly after good silicon is available in reasonable volume. At that point, why should one spend $8-10k for that hardware from the likes of HP, Compaq, Dell and others when one can build it for $2k (or even less)? In other words, has Intel finally done in most of their customers by obliterating all the other CPU choices (except IBM Power4 [& friends G4, et al] and AMD Hammer) and turned the remainder of the marketplace into raw commodity goods? Lest you defend the other CPUs... Sparc is dead,
Sun doesn't have the money (more than US$1B we'll guess) to do another round. PA-RISC is done, as HP has
given away the architecture group. MIPS lacks
funding (and perhaps even the idea people at this point). Alpha is
gone too (also because of the heavy investment problem no doubt). Most other CPUs don't have an installed base that makes any difference, especially in the high end computing world. So what's next? I don't like the single track future that Intel has just because it is a single track!"
Having recently participated in an NDA from Sun regarding the SPARC processor (and even with the knowledge I had walking into the meeting), SPARC is not dead or dying. In fact, I'd say that Sun squarely recognizes it as a strength. Their competition (HP for example), however, is wishing they didn't knife their baby.
As far as money to go another round, remember, Sun doesn't fab CPUs. What Sun does is design them, and they turn it over to Texas Instruments for production. And TI has their own reasons to keep up-to-date with the latest production technologies, so Sun doesn't eat that cost.
BTW: I really wish that I could talk about the SPARC presentation. I liked it a whole lot better than the NDA I attended with HP talking about their Itanic future.
I may be off base on some of the details, but Sun has a unified approach from top to bottom, from tools to silicon for the systems they plan to deliver. I doubt it will just throw in the towel. Ultimately, Sun ships iron, and they lead the market in their segment.
I don't see the basis for your assertion, and where you pulled 1B out of for cost I also don't know.
Alpha is AMD now, as that's where a good chunk of the people went. MIPS is still kicking, with the 14000 so far, but I won't speak to the future of that chip line. There's a lot of chip heads on this site with much better info than I on many of the lines.
One decent, although dated summary is here
Please tell me there's more information you're basing this on than consumer workstation marketshare....
A fast CPU is nice, but how about upgrading the rest of the standard PC architecture and peripherals to the same level?
:P
Weren't we all suppose to be using high-speed serial connections by now instead of a cocktail of SCSI (1/2/3, wide, fast, hold the mayo), IDE (ATA-33/66/100), parallel, 8 bit serial, USB, Firewire, PS/2, PCI, ISA (which is finally disappearing), etc. Heck, I'd be happy if the motherboard ran at even half to a third the speed of the cpu.
Using a 20 year old peripheral port on last weeks multi-gig cpu is like sucking a McDonalds shake through a coffee stirrer!
Rewriting standard applications to take advantage of the Itanium is one thing. However, companies that need a $10k+ server usually have programs that are specialized. After 20 years of the x86 standard there's a large codebase, although given a few improvements along the way. If you read the FreeDOS article a little while back companies were still running DOS in production systems, because it *works*. Porting it to Itanium will be a lot worse than porting it to x86-64 and Hammer. Let's face it, the hardware cost is usually minimal today. Software programmers however, are not cheap.
Kjella
Live today, because you never know what tomorrow brings
Not likely, it would take a couple of weeks max for the first compilers to appear
You obviously know nothing about Itanium, EPIC, VLIW, or pretty much anything else on this topic.
The issue isn't whether or not there's a compiler available. The issue is how GOOD the compiler is. In the case of a Very Large Instruction Word (VLIW) CPU like the Itanium, the compiler is the bottleneck for system performance. Why? Because the premise of these CPUs is that while they have a low clockspeed (750-800 MHz for Itanium), they execute many instructions per cycle - 10 or more. So while "slower", they get more done per cycle, resulting in a faster overall execution. It's up to the compiler to properly structure the executable machine code to take maximum advantage of this layout and keep all execution units of the CPU busy at all times, as well as reduce disseparate memory accesses and so forth.
The intial compilers that are released with these machines do it, but not as well as they could. In fact, compiler writers are still trying to grasp the issues with pipelining on modern CPUs and their much lower number of execution units, and this is without utilizing special instructions that explicitly do non-conflicting operations at once. We're still years away from writing fully optimized compilers for contemporary CPUs. And while there's been a great deal of work done on VLIW already (prior to Itanium), there's even more yet to be done. A decade for a "good" compiler is probably optimistic.
You may be wondering, what's the point anyway? If VLIW is so damn hard, why bother? Just ramp up that clock speed and get more CPU power! Well, that's nice, but it doesn't work in reality. We're starting to bump up against physical limitations in CPU speeds. Electrons are not magical particles that travel instantaeously. They are limited to slightly under the speed of light, which means roughly 1 cm per nanosecond. This doesn't seem to be a big deal until you realize that a 2.0 GHz CPU means each clock cycle is 0.5 nanoseconds. So if you have to fetch an instruction or data from main memory, and that memory is a mere 5 cm away, under optimal conditions you've just sat around for 10 clock cycles waiting on that memory to be fetched. This is ignoring the fact that there's propogation delays, latch delays, and other things. So go ahead, pump that CPU up to 10 GHz and waste even more clock cycles waiting on data. That or redesign the entire thing, expect the compiler to do the work and properly feed you data and instructions such that you can do 10x as much in the same amount of time, and all with no wasted CPU instructions.
That's the theory at least.
Reality is that not only does the compiler have to properly organize the machine code, it also has to have some idea of what the code is doing to do so. Compile the code w/ profiling, run the code against a "realistic" data set, then recompile it again feeding it the profile data. Many compilers can do this now, but it's rarely done. Because it's hard to guess a "realistic" data set, it's hard to acquire the same, how you expect the code to be used and how it actually is used are rarely the same, and there's more development time involved in all of this. So most companies don't bother. And despite what I said above, 2.0 GHz still hasn't reached the point where the CPU is sitting on it's ass more than it's doing work. Until we start approaching that point there's little incentive to put in the R&D time necessary to switch to a new CPU archictecture.
And, of course, on top of all of the above is the issue that Joe Sixpack will invariably see 2 GHz as faster than 750 MHz no matter what. Have fun with that one.
No, you can't build something like a Netfinity (oops. er - xSeries eServer) in your garage for $2k. Built into a high-level xSeries is:
1) Hot-pluggable power supplies, drives, and PCI - slots.
2) Built-in hot-plug SCSI
3) Integrated service processor for diagnostics (essentially a computer within a computer)
4) Extremely well-tested box. (Very important to do integration testing on high-end units.)
5) Very nice, serviceable, rack-mount chassis
6) Crap-load of PCI slots
7) Light-path diagnostics. (Lets somebody without training figure out what's broke.)
8) IBM Director
9) Well-designed cooling that would be impossible to achieve with a garage box. (Do you know how to do airflow modeling?)
10) Support.
The list goes on...
Yes, they will become a commodity, in that you will be able to get them from multiple major manufacturers, but don't expect to build it yourself in your basement anytime soon.
SirWired