Happy Birthday! X86 Turns 30 Years Old 362
javipas writes "On June 8th, 1978 Intel introduced its first 16-bit microprocessor, the 8086. Intel used then "the dawn of a new era" slogan, and they probably didn't know how certain they were. Thirty years later we've seen the evolution of PC architectures based on the x86 instruction set that has been the core of Intel, AMD or VIA processors. Legendary chips such as Intel 80386, 80486, Pentium and AMD Athlon have a great debt to that original processor, and as recently was pointed out on Slashdot, x86 evolution still leads the revolution. Happy birthday and long live x86."
Backward integers forever! (Score:1, Insightful)
Yep, lots to be happy about. Long live mediocrity.
I wish it would just die. (Score:2, Insightful)
Legendary? (Score:0, Insightful)
But I guess we have the Pentium 4 to thank for conditioning the masses to think that clock speed equals performance to the exclusion of all else, and that it's okay for a CPU to burn 100-150 watts all by itself.
Intel has always been a P.O.S. (Score:4, Insightful)
Re:I wish it would just die. (Score:3, Insightful)
But you see, the thing with standards is that the longer they live, the harder they are to kill. At 30 years old, the x86 ISA is damn near invincible now.
Re:Doing it right -- mostly (Score:5, Insightful)
While I'm sure thats how the script was repeated in Intel, suggesting great generosity ("And we give it away for free!"), what choice did they really have? IBM's whole Micro Channel Architecture fiasco showed what licensing did to adoption of new advances in system architecture and integration.
Intel made some horrible design decisions. (Score:5, Insightful)
On that day, he was very sad. Intel made some horrible design decisions. We've had to live with them every since. Starting with the fact that assembly language programming for the X86 architecture is really annoying.
Re:Overcoming Limitations (Score:5, Insightful)
Re:Itanium sank (Score:5, Insightful)
Die already ! (Score:5, Insightful)
Oh my god, no ! Die already ! The design is bad, the instruction set is dumb, too much legacy stuff from 1978 still around and making CPUs costly, too complex and slow. Anyone who's written assembler code for x86 and other 32-bit CPUs will surely agree that the x86 is just ugly.
Even Intel didn't want it to live that long. The 8086 was hack, a beefed up 8085 (8-bit, a better 8080) and they wanted to replace it with a better design, but iAPX 432 [wikipedia.org] turned out to be a desaster.
The attempts to improve the design with 80286 and 80386 were not very successful... they merely did the same shit to the 8086 that the 8086 already did to the 8085: double the register size, this time adding a prefix "E" instead of the suffix "X". Oh, and they added the protected mode... which is nice, but looks like a hack compared to other processors, IMHO.
And here we are: we still have to live with some of the limitations and ugly things from the hastily hacked together CPU that was the 8086, for example no real general purpose registers: all the "normal" registers (E)AX, (E)BX, etc. pp. are bound to certain jobs at least for some opcodes. No neat stuff like register windows and shit. Oh, I hate the 8086 and that it became successful. The world could be much more beautiful (and faster) without it. But I rant that for over ten years now and I guess I will rant about it on my deathbead.
Re:Legendary? (Score:4, Insightful)
I do believe that was first done by an x86 CPU, the NexGen Nx586 (the predecessor to the AMD K6...)
Re:A few tweaks, and... (Score:5, Insightful)
NEC V20? (Score:1, Insightful)
-- kickin it old school IBM PCjr style.
Re:Intel has always been a P.O.S. (Score:2, Insightful)
Re:A few tweaks, and... (Score:5, Insightful)
But would the extra RAM have been affordable to typical users of these programs at that time?
I remember fighting for expensive upgrades from 4 to 8 MB RAM at my workplace back in the early 90's. At that time PCs had already been able to use more than 1 MB for some years. So the problem you are referring to must have been years earlier where an upgrade from 1 to 2MB might probably have been equally expensive.
Re:Itanium sank (Score:2, Insightful)
How could Intel have got it so wrong? as Linus said "they threw out all of the good bits of X86".
It's good to see however that Intel have now managed to product decent processors now the GHz wars are over. In fact it's been as much about who can produce the lowest power CPU. AMD seem to just have the edge.
Maybe having vision is overrated. Evolution has no vision it just hacks stuff blindly. But it designed your brain. Conscious engineers planning for the long term can't do that.
Re:Die already ! (Score:2, Insightful)
Re:Out of interest... (Score:3, Insightful)
On top of that, it's probably subject to change with each micro-architecture.
Re:Out of interest... (Score:3, Insightful)
Re:Die already ! (Score:3, Insightful)
Most software developers care more about things like good development tools and the convenience of binary compatibility across a range of devices from supercomputers to laptops to cell phones.
Cross-compiling will always suck and emulators will always be slow. As lower-power, more highly integrated x86 chipsets become more widespread I expect to see the market for PowerPC, ARM and other embedded architectures shrink rather than grow.
Re:How Long? (Score:5, Insightful)
maybe that will finally be enough to run vista at a decent speed.
[/bashing joke]
"Dawn of a New Era" (Score:2, Insightful)
Re:Die already ! (Score:5, Insightful)
The attempts to improve the design with 80286 and 80386 were not very successful... they merely did the same shit to the 8086 that the 8086 already did to the 8085: double the register size, this time adding a prefix "E" instead of the suffix "X". Oh, and they added the protected mode... which is nice, but looks like a hack compared to other processors, IMHO.
The first instinct of the engineer is always to tear it down and build it again, it is a useful function of the PHB (gasp!) that he prevents this from happening all the time.
Re:Itanium sank (Score:5, Insightful)
Back in the 80's it was a lot cheaper to develop a processor. They were considerably simpler and slower. The reason there were so many processor architectures around back them was that it was feasible for a small team to develop a processor from scratch. It was even possible for a small team to build, out of discrete components, a processor that was (significantly) faster than a fully integrated microprocessor, e.g. the Cray-1.
As the semiconductor processes improved and more, faster, transistors could get squeezed onto a chip, the complexity and the speed of microprocessors increased. Where you're at today is that it takes a billion dollar fab and a huge design team to create a competitive microprocessor. x86 has succeeded because there is such a torrent of money flowing into Intel from x86 sales that it is able to build those fabs and fund those design teams.
PowerPC, for example, was a much smaller effort than Intel back in the mid-90's. PowerPC was able, for a short time, to significantly outperform Intel and remained fairly competitive for quite a while even though the design team was much smaller and the semiconductor process was not as sophisticated as Intel's. The reason for that was that the architecture was much better designed than Intel, making it easier to get more performance for fewer $$. Eventually, however, the huge amount of $$ going into x86 allowed Intel to pull ahead.
Re:Its hard to believe ... (Score:2, Insightful)
Re:Doing it right -- mostly (Score:0, Insightful)
Re:How Long? (Score:3, Insightful)
Re:How Long? (Score:3, Insightful)
Linux can just recompile them and Apple only supports hardware they distribute, so that makes it easier.
Re: Dual instruction sets? (Score:2, Insightful)
Oh wait, that's been done. It's called porting to a different, more elegant and/or power efficient architecture (like ARM, Mips or other). What you need for that is source code for the software. If you have source code for all the software you need, nothing keeps you from moving to a better CPU architecture. If you don't (like with closed-source apps on Windows), then you can't.
If manufacturers of those mini-PC's like the Asus EeePC can take a hint, they'd do the smart thing and move the Linux-based versions onto a more power-efficient architecture. You'd lose the binary compatibility, but that would be a small loss if you're running Linux and not do serious PC gaming anyway. In return you could have vastly improved battery life for the Linux-based versions.
Re:How Long? (Score:5, Insightful)
The question is whether a processor running its native instruction set would be faster. From what I can tell the native instruction format of a modern x86 is wider than the x86 equivalent. Suppose the uops in the pipeline are 48 bit - a 32 bit constant and a 16 bit instruction. That is quite a bit larger than a typical x86 instruction. Wider instructions take more space in Ram and cache. You don't need to decode them, but the extra time fetching them kills the advantage.
And what is native is very implementation dependent. An AMD chip will have a very different uop format from an Intel one. Actually even between chip generations the uop format might change. Essentially Risc chips tried to make the internal pipeline format the ISA. But in the long run that wasn't good. Original Risc had branch delay slots and later superscalar implementations where branch delays work very differently had to emulate the old behaviour because it was no longer at all native. So if you did this you'd get an advantage for one generation but later generations would be progressively disadvantaged. Or you could keep switching instruction sets. But if most software is distributed as binaries that is impossible.
Re:How Long? (Score:3, Insightful)
The problem is NOT Microsft.
The problem is end users. They want to use their existing x86 hardware and software. They aren't really interested in not having drivers for anything more than 3 months old, and running all their existing software at 30-70% its current speed.
Look at the x64 versions of Windows. It highlights exactly the problem. XP x64 was crippled by lack of drivers, and Microsoft HAD to force the issue with Vista because the x86 ram limit was starting to hold things back. But even today most customers don't WANT the x64 edition. This issue isn't really MS. If they could abandon x86 and keep their customer base, they would, in a heartbeat.
Linux also supports other architectures, but the G5 as a linux platform is a pretty niche thing to do, since you have to compile a lot more stuff from source and not all of it is cpu agnostic, plus no proprietary linux software will run and you can't stick Windows into a VMware VM, etc.
yes I know a decade ago NT 4.0 did run on PowerPC, and even a couple of alpha chips.
And MS could release a version for another CPU within a couple months if they really wanted to, if not faster. But who is going to step up and rewrite all the drivers? Who is going to step up and rewrite all the applications? Leaving that to the 3rd party vendors? They aren't interested in anything but their current project... they aren't going to go back and recompile squat. Hell, most STILL aren't releasing x64 native code.
Apple with a fraction a of the software guys can keep their OS on two major different style of chips PowerPC, and Intel x86, along with 32bit and 64 bit versions of both.
1) Apple controls the drivers so that part of the issue is largely solved. Of course your 3rd party hardware might not work after they switch, but at least all the apple hardware works.
2) Apple didn't want to switch. They had to. Intel was kicking butt in performance, while IBM couldn't even deliver a mobile G5. Consumers were starting to get twitchy about the fact that Windows PCs were getting markedly faster, while mac laptops were still stuck on G4s.
3) The performance gap from the G4/G5 to the intel stuff had gotten so bad, that by the time Apple switched, running PPC code in emulation on intel was actually an improvement in some cases, and in most cases at least comparable to running on the (slower) native hardware.
4) Apple is killing off the PPC. Much new software is already intel only, and the next release of OSX is rumoured to be intel only.
Apple is really a whole other ball game. As for solaris... that's the same as linux... but even more niche. How many people do you know running solaris on ppc?
Re:How Long? (Score:3, Insightful)
The biggest problem is probably like with 64-bit Windows: drivers.
No, the biggest problem is applications . Same "problem" that stops people switching from Windows to $OS_DU_JOUR.
The second biggest problem, of course, is basic economics. What other hardware platform offers even the slightest amount of ROI for Microsoft to expend the effort on porting Windows to ? Where's the business case ?
Re:How Long? (Score:3, Insightful)