IBM joins Trillian project 100
IBM will be
joining the Trillian project to port Linux to Merced. The other
members of Trillian are Intel, VA Linux Systems, SGI, Hewlett-Packard,
and Cygnus Solutions. Linux will be shown
running on a
simulated Merced today at the Linuxworld conference.
Re:Merced Sucks. Go with the Alpha. (Score:1)
Re:No answer, but info (Score:2)
To do what, specifically?
To switch between two separate instruction sets, I'll believe. You need more decoding logic, but it can be done fairly easily.
To allow programs to be written in microcode, I doubt - microcode has a very low code density, which leads to many, many problems. RISC is just as easy to optimize, so you don't gain much for your pains.
Re:Satans 666 chip. (Score:1)
Re:K7 (Score:1)
Where must one make the optimisation? Is it possible to have a compiler that will automatically take advantage of the features? or do you have to explicitly write code into your app that will know what to do? (I've seen this, for example, in mpg123 - there's a compile-time option to use 3dnow if you have an amd chip).
Thanks
You can use the alpha with 32-bit pointers ... (Score:1)
DEC (uh, Compaq) has a term for this usage: it is "taso" (for truncated address space option) and it is there to ease porting of crufty old-style "an int is a pointer" code. Does anyone remember the Vax?
One could write an entire operating system in TASO mode. Few have, just 'cause it is so elegant to use 64-bit pointers. But if you have a runtime system with data structures dominated by pointers, using TASO mode can save a lot of space.
Oh, and I've seen NT running on the Alpha. So Microsoft can run 64-bit code. And the IA64 does have compatibility mode for old-school IA32 (nee x86) code.
Re:Skipping CISC to RISC translation (Score:2)
Ok... Their marketing department calls these RISC instructions, and I call them microcode bit vectors. The article you cited points out itself the differences between this and conventional RISC instructions - RISC instructions don't contain as much internal control state information. They also are usually one machine word in size (32 bits on most PCs, 64 bits on most workstations). These bit vectors are much longer, which leads into the main problem with this approach, which I mentioned in other responses - very low code density.
By writing in microcode, you skip any decoding latency that might exist, but you end up having to transfer several times more information than you otherwise would. This means it takes several machine words to specify each instruction, and several bus cycles to load each instruction (full bus speed != one instruction per bus clock). You could put in a wider memory bus, but the same problem applies - your instruction stream bandwidth just went down a lot. As memory bandwidth is one of the main limiting factors for system performance, this will hurt, a lot. Additionally, the instruction cache can suddenly hold far fewer instructions - you either need a bigger cache to compensate, or suffer through many cache misses.
I am very surprised that NextGen actually built a chip using this approach. It's an interesting idea, but as I state in other messages, conventional RISC is almost as easy to decode and doesn't suffer from the code density problems described above.
The question is, does the K7 bus do what the Nx586 bus did and what the Socket 7 motherboard bus did not -- can it bypass the 80x86 decoder?
I strongly doubt it. No mention of this was made in any of AMD's releases, there is no pressing market demand for it, and it would probably _worsen_ performance, as described above. What they _could_ do is allow an additional RISC instruction set, which would accomplish much the same thing, but it is open to question whether the (very substantial) additional design effort would be worth it for their target market.
Intel is doing something similar to this with the Merced, with x86 and VLIW modes, but that design has its own problems.
Only slightly unrelated point (Score:1)
Re:K7 (Score:1)
Yes it's x86 compatable, BUT... (Score:1)
Think about it: the entire point of the Merced is to place the burden of optimizing a processor's operation on the compiler rather than the processor itself. Merced's performance is totatly reliant of the quality of the compiler. In x86 most of the work is done in hardware. But the Merced is not an x86 processor, it is an IA-64 processor with x86 emulation. This means that the Merced will simply lack the hardware to optimize x86 operations. It propably won't be able to do any branch prediction, out of order execution, and will be unable to use more than one pipeline. Basically, it will run like a high clocked 386, if that well. Did I mention that it will also cost a freakin fortune? I don't know why they even bothered to include x86 compatability. It sure as hell isn't worth anything. The Merced needs its own software in order to succeed.
Re:Anyone know about The Enemy's plans? (Score:1)
I know alpha and merced are wildly different. I think maybe we need to watch MS a little more carefully.
Re:Anyone know about The Enemy's plans? (Score:1)
that's exactly true. Don't they have a neglected version of NT for alpha processors.
Isn't alpha 64 bit?
Yeah, alpha chips are 64bit, but NT isn't. It runs in "32bit emulation mode." Meaning that NT doesn't take full advantage of the architecture, and it also probably means that there are some serious flaws in M$'s code that keep them from easily porting to 64bit. Expect M$ to get left in the dust by Linux on the IA-64.
MS delaying NT64 somewhat -favours- intel (Score:1)
Trillian? (Score:1)
Re:K7 (Score:1)
K7 optimization is still possible. Turn off all Intel-specific instruction order constraints. That will give the compiler more options for other optimizations that depend on reordering.
Re:Microsoft is way ahead, actually (Score:1)
only if you don't ever turn your computer on
K7 (Score:1)
Oooooh!!@# A simulated Merced! (Score:1)
Re:K7 (Score:1)
Re:Merced Sucks. Go with the Alpha. (Score:1)
Intel has the fabs to crank out millions of Merced chips at affordable prices. How many 21264 chips can Alpha Processor Inc. ship? The last time I checked, 21264 motherboards and systems were very expensive.
Re:Merced Sucks. Go with the Alpha. (Score:1)
WinNT on the otherhand, can't. It has some major problems, or otherwise, NT/alpha wouldn't run in 32bit emulation mode on the alphas. M$ will most likely have to rewrite massive portions of windows to get a version that takes full advantage of the IA-64 architecture. So while I never plan on buying one, Linux is going to school windows in performance on the IA-64, what should be MickeySoft's home turf. Even though Linux already out performs M$, it will be even more of an advantage for Linux.
Just another victory for Linux. Besides, one of Linux' current strengths is extreme portablity.. Why leave Intel in the dust now? The more hardware supported, the larger the potential install base, and some people are going to buy the Merced chips. Personally, I have been eagerly waiting for this to happen...
Jeff
Re:Merced Sucks. Go with the Alpha. (Score:3)
The Alpha is an established 64-bit standard, and I can understand its manuals.
Yes, the Alpha is very good.
I cannot understand the manuals for the Merced.
You don't have to. It's the kernel, gcc and glib people who do. Write in C, it's safer.
It is possible, though usually inefficient, to hand-code for the Alpha. It is impossible for the Merced.
Hand coding is never impossible. A big pain in the burro, but not impossible.
Alpha already is running Linux. Not so Merced.
As the article indicates, Merced is already running Linux, to the extent where Merced exists. We're already ahead of the NT and Monterrey projects for Merced.
Why are we wasting time with the Merced? It is nothing but welfare for Intel.
Two reasons. First, we want to support everything, that would include Merced by definition. Second, Merced will have lots of marketting bucks behind it, that will make it popular. We certainly should support the more popular platforms, even if they have deficiencies.
Alpha has been around for years, and it has demonstrated its worth again and again. It is the architecture of the future.
I agree.
Who needs Merced?
Intel does, to survive the future. The rest of us do, because Merced will make 64 bit platforms popular, and in the computer world, popular becomes inexpensive very quickly.
----
Re:K7 (Score:2)
----
Re:Sad... (Score:1)
The alpha hack^H^H^H^Hport was done after the processor was already available. Seeing as Intel's implementation of IA-64 isn't widely known (it requires an NDA for the info) this can't be a project that a few hackers work on in their spare time.
Besides, IA-64 is a MUCH different architecture than the Alpha. I'd be much more interested to hear about the progress of compilers (which seems to be the most difficult part).
Incidentally, does anyone know if gcc will be able to easily compile on EPIC architectures? This seems like a pretty non-trivial change...
-NooM
Sad... (Score:1)
I guess I just don't get why the port is such a major project to take all this public effort. Most of the other ones have been midnight hacks that have gotten apologized for after the fact. I'm more curious as to why it ISN'T done...
This is interesting.... (Score:1)
is still a ways off and I thought it'll be
targeted at enterprise users? Or is it now
a consumer chip?
On the flip side, if this would get more apps
brought over the Linux side this is a great
thing!
I think it's a win-win for Linux. Hopefully
it'll benefit all the supported hardware
platforms.
In the short run I think it'll benefit Linux
by associating it with Intel's 'next greatest
chip' and by promoting more companies to port
apps over.
ed
Re:Merced Sucks. Go with the Alpha. (Score:1)
Skipping CISC to RISC translation (Score:2)
I'm going into my fourth year of Computer Engineering, focusing on chip design. The short answer is that it isn't possible to bypass the instruction translators. They aren't translators per se, but something closer to macro expanders.
A CISC instruction (or to a lesser extent, even a RISC instruction) is a concise way of saying that you want the chip to do something fairly complex. For both RISC and CISC processors, these instructions have to be expanded out into a series of truly elementary hardware operations for the chip to perform. RISC instructions tend to be a lot simpler, and are a lot closer to the final "microcode" that controls the various parts of the chip, but they still need _some_ decoding to be processed.
The statement that the K7 (or Pentium-whatever) has a "RISC core" is a bit of a misnomer. What they actually do is allow different tasks required by a CISC instruction to be executed independently. This could be thought of as breaking it into a series of equivalent RISC instructions, but no such instructions actually exist (though you could argue that "micro-ops" and "macro-ops" are close).
Short answer, as above: You can't bypass translation and write in native RISC, because there isn't really a native RISC to write in and analogous translation would still be required no matter what sets of opcodes you were using.
Hopefully this was interesting for anyone that read this far
Re:AIX... (Score:1)
Which, clearly, you do not. Are you suggesting IBM will port Montery over to the rs/6000? Or are you suggesting they'll ditch the powerpc chip in favor of the ia64? Either way, you're as clueless as you are anonymous.
And, who the hell cares if IBM 'competes' with SGI? SGI isn't exactly a juggernaut of the industry these days..
But I digress. The really interesting thing here is monterey. What _IS_ IBM thinking they're going to do with it? I have a hard time believing they'll dump it, since they're well known for holding onto dead projects till they crumble into dust.
Maybe they just want to get ahold of the specs so they can see how ia64 holds up to the new powerpcs
--
Blue
Re:Sad... (Score:1)
1) Intel is hyping the chip quite a bit. Compaq doesn't hype the Alpha. So there is generally more information, or rumors, about said chip.
But in order for them to hype it properly, Intel is going to need an OS that they can show their chip's new (new for Intel) 64 bit processing. Which brings me to point two.
2)They need to help out the Linux project if they want an affordable OS on their chip when it comes out (affordable being something that the average user will be willing to pay). It isn't like Intel is going to go out and hype that Solaris will run on the Merced chip, and there is no way in the pits of Redmond that MS will get NT 64 out in time.
3)The article is about how IBM is supporting this. Sure the Intel symbol is what is being used for the article here on Slashdot but the big news is that IBM is helping port Linux over to Merced. This is big news, really big news.
4)Linux for the Alpha is already out there. There isn't going to be any news discussing porting Linux over to the old Alpha because it already exists. Also, when something does happen to the Alpha chip, Slashdot does report it.
Re:Trillian? (Score:1)
adam
Re:Anyone know about The Enemy's plans? (Score:1)
But the real story is that Intel apparently intends for Linux to be ready from the start, whether Microsoft is ready or not. In the past, MS has had a window of time where they could develop and optimize at their own pace, without having to worry about a competitor beating them to the punch. With Merced, they'll be under pressure im a way they haven't been in the past.
Merced is shaping up to be the watershed platform for Linux. It wouldn't surprise me to see it drmatically outship Windows Whatever in the first year, especially since new Intel CPUs tend to go into servers first.
16-bit Windows (Score:1)
Beowulf (Score:1)
Alpha doesn't have a '32-bit' mode.. (Score:1)
i guess what MS did was to compile everything with a 32bit address space, and just pad out the rest of the address space.
i don't know the details, but there was a discussion on axp-list about the very same thing: ie how to get apps to run in a 32bit address space on alpha. (eg for netscape which isn't 64bit clean).
Alpha doesn't have a '32-bit' mode.. (Score:1)
i guess what MS did was to compile everything with a 32bit address space, and just pad out the rest of the address space in some way.
i don't know the details, but there was a discussion on axp-list about the very same thing: ie how to get apps to run in a 32bit address space on alpha. (eg for netscape which isn't 64bit clean).
Re:Yes it's x86 compatable, BUT... (Score:2)
It's there to provide an Intel-brand x86-compatible chip after Intel switches to IA64. Current users who want to upgrade and still want to buy Intel will buy it, which gets them "hooked" on the new architecture. If Intel broke compatibility, they would lose their market. x86 clones would be chosen by the masses, and people who wanted a high-performing non-x86 system would choose other processors.
If, on the other hand, people can upgrade their x86 "workstations" to Merced "workstations", they can still run their old software, while software written with the Merced in mind gets a speed boost.
Think about it: the entire point of the Merced is to place the burden of optimizing a processor's operation on the compiler rather than the processor itself. Merced's performance is totatly reliant of the quality of the compiler.
For the VLIW instructions, yes. However, it wouldn't cost them much space to put in x86 optimizations. Heck, most of them are already present in the Merced hardware - pipelining, superscaling, and branch prediction are still there. x86 emulation would just require a second instruction decoder and a bit of extra glue logic.
The reason that the compiler is a bugger is that it's difficult to use _VLIW_ properly outside of hand-coded assembly.
IMO, the Merced will either take a 1.5x speed hit over straight x86 clones, or will require 1.5x as much silicon. I'm betting that Intel will throw extra silicon at it and wind up with a chip that runs x86 code at reasonable speed but that costs twice as much as a Pentium-III to fabricate.
Did I mention that it will also cost a freakin fortune?
I strongly suspect that they'll release a cheaper low-end version with smaller cache, just as with the Celeron/Pentium/Xeon spectrum. They need something to offer in the x86 regime, and they need consumers to upgrade to something Merced-compatible if they want to keep their market share while moving on with the Merced. If they don't do this immediately, they'll do it reasonably soon afterwards.
Re:Someone will have to port this too! (offtopic?) (Score:1)
"NT64 was a 64-bit rewrite of a 32-bit extension to a 16-bit patch of an 8-bit OS written for a 4-bit processor by a 2-bit company that was crushed by Linux, which came along not 1 bit too soon."
----------------------
"This moon-cheese will make me very rich! Very rich indeed!
Why Alpha/Linux is NOT popular... (Score:2)
GCC is a fairly good compiler for x86, even when compaired to commercial compilers. GCC is really getting better every day for x86, literally.
But if you compare Alphas with True64-UNIX (formarly DEC-UNIX) and commercial compilers to Alphas running Linux using GCC, there is a HUGE gap in preformance. There is a simple solution though... Get the GCC guys some 21264's ASAP ;-)
BTW, IBM is seems to putting faith into other people's CPU's for Linux ports is a popular idea now, check MU for a story [current.nu] on IBM porting Linux to PowerPC 405.
Re:poem (Score:1)
Re:Will Linux be ready for Merced before NT? (Score:1)
Yup. Intel wants to avoid a repeat of Microsoft's Windows 2000 challenge disaster on their new processor.
Pure heresay but... (Score:1)
There are all kinds of weird and wacky TR bits that someone's played with and found interesting things.
... not that it makes much difference, I just found it interesting.
Andrew
Re:it sucks (Score:1)
So, like, why is Intel doing this? (Score:1)
Re:No answer, but info (Score:2)
I am using "microcode" to refer to the final signal patterns on the control lines during each clock, which may not be the standard usage. Re. MUX vs. table lookup, both take a significant amount of time, which is what I am getting at. By making your instruction opcode a huge bit vector specifying the state of all control lines for the current clock and possibly the next few clocks, you could eliminate the decoding, but at the expense of a silly amount of code bloat, which IMO is impractical (among other things you'd need several memory reads to read each opcode).
I readily agree that complicated CISC translation takes longer than RISC translation, but IMO going any farther than RISC gets impractical very quickly.
Re:Skipping CISC to RISC translation (Score:1)
To quote the June 1994 issue of
Byte [byte.com] magazine:
The question is, does the K7 bus do what the Nx586 bus did and what the Socket 7 motherboard bus did not -- can it bypass the 80x86 decoder?
Anyone know about The Enemy's plans? (Score:2)
Now, I know that their development model is in no way open, but I'm still surprised that I haven't heard reports about the transition to Win64 (or whatever it will be called). Perhaps they are so bogged down trying to get W2K to a beta stage so they can finally ship the thing that they aren't focusing on IA-64 yet.
anyone know?
--Lenny
Re:Merced Sucks. Go with the Alpha. (Score:1)
IA-64 has been accepted by most of the major companies out there as the standard of the future. It is bigger than just Merced. The port to IA-64 is a big win for Linux.
Whether you _like_ the architecture or not it is probably going to be a powerful force.
Re:Merced Sucks. Go with the Alpha. (Score:1)
Re:Someone will have to port this too! (offtopic?) (Score:1)
SirSlud
Re:Merced Sucks. Go with the Alpha. (Score:1)
Merced's popularity is not guaranteed...yet. Intel has been able to get people to buy 8086-to-Pentium3 up to now, because there's a large installed base that is locked into x86 compatability. The size of the installed base has enabled economy of scale, which has reduced the price to the point where x86 chips are actually desirable even if you're not locked in. That's why so many Linux users (who never really had any serious need for binary compability with 1981 software) are running on x86.
But everything changes when they break compatability. If Merced isn't x86, then both the locked-in and the scale advantages evaporate. Well, the scale advantages don't completely evaporate, because Intel still has the factories, but they play a lessor role.
The upshot is that as Pentiums start coming to an end, this will be the first time in 20 years that many people will actually be able to choose the best CPU based on technical merits rather than market forces. That is exciting! May the best CPU win!
---
Have a Sloppy night!
Monterey... (Score:1)
Betcha Monterey gets dropped in favour of Linux.
Maybe Sequent or SCO carry on alone, but it'll probably not amount to much.
Re:Anyone know about The Enemy's plans? (Score:1)
They did some ugly things to the size of C data types to make it easier to port Win32 software to Win64. Longs are still 32 bits and they added a new type for 64 bit integers. Barf.
Re:Sad... (Score:1)
Re:Sad... (Score:1)
Alpha isn't one of the pieces Compaq really wanted when Palmer sold out. They wanted the Enterprise desktop and figured they could sell Wintel boxes into it better than Alpha. Hyping Alpha directly competes with their core business. They will quietly continue to sell servers and support to the current customer base while weaning them from it.
Re: 2
The MS OS honeymoon is over. Sure they'll jump onboard but the fact that it's an architecture change. MS has it's hands full with the three OS updates it has in the pipe. I seem to remember rumblings of a Unified Windoze OS... 8^)
Re: 3
IBM has jumped on the bandwagon in a major way. The DB2 port and the other announcement this afternoon with the Lotus Notes/Domino port (remember there's BLUE underwear under that yellow and black outfit).
Re: 4
That was my total point. 64bit is old news but the release makes it sound like a major feature of the port. New chip is new chip is new chip.
poem (Score:1)
where are you? dead?
I've looked far, i've looked long,
your future is like a sad sad song.
My heart wonders to other places,
with Alpha's, K7's, and G4's in clear cases.
Alas, I'm am tired, alas I am sick,
of waiting for a processor that won't suck dick.
Why? To stick it to MSFT. (Score:1)
But technically? Nah, no real reason.
Realistically, though, if there isn't Lintel stuff for IA-64, MSFT will win somehow. Don't know how, don't know when, but
Also Linux will be out and stable before W2K (Score:1)
When MSFT can't crank out a fast, efficient, stable release for a new chip as fast as a bunch of chaos coders, they're doomed.
Re:Anyone know about The Enemy's plans? (Score:1)
Well, the lag between the Compaq Deskpro 386 and Windows 95 was about nine years. So if you extrapolate, it should occur at about the same time that aliens turn Jupiter into a new star: 2010.
---
Have a Sloppy night!
x86 compatibility (Score:2)
My understanding is that the Merced is x86-compatible. They added a new processing mode in which the Merced's new instruction set and new register structure are accessible, I think.
Re:Anyone know about The Enemy's plans? (Score:1)
Considering how MS likes to hype all ot their OS upgrades a 2 years in advance, I'd guess their progress for Merced is at least 3 years away from completion. Of course MS products are always a tear late.. so I figure 2004.
On a serious note I think that like all things Intel IA-64 will be hyped to all hell, and every one will need one. If MS is more then 6 months late with a 64 bit version of NT and Linux for IA-64 is out with the release of Merced I think MS stands a good chance of being left in the dust.
Ex-Nt-User
Re:Someone will have to port this too! (offtopic?) (Score:1)
Of course maybe that's just silly.
Re:Merced Sucks. Go with the Alpha. (Score:1)
Microsoft never really got away from the 16bit code, even in Windows 98 (supposedly...I have no first hand knowledge of this, but Dr. Dobbs Journal has had articles on it). I wonder if Windows for IA-64 will still have 16bit code and if Intel will include 16bit for very-backward compatibility.
Re:Satans 666 chip. (Score:1)