HyperTransport 3.0 Ratified 179
Hack Jandy writes "The HyperTransport consortium just released the 3.0 specification of HyperTransport. The new specification allows for external HyperTransport interconnects, basically meaning you might plug your next generation Opteron into the equivalent of a USB port at the back of your computer. Among other things, the new specification also includes hot swap, on-the-fly reconfigurable HT links and also a hefty increase in bandwidth."
External HyperTransport? (Score:4, Funny)
"Hum... I can't quite afford a whole new system or even a motherboard and two new procs... I'll just add a new one to the back of an existing one"
At last! The day of easily being upgrade to a multi-proc system may soon be at hand! (assuming they also have some sort of... external hub device).
Re:External HyperTransport? (Score:5, Insightful)
Point being, you'll never be able to plug a new opteron into _anything_ that's sitting in your closet right now.
Re:External HyperTransport? (Score:2)
That's really, really limited -- the PCI bus isn't even considered suitable for 3D graphics cards anymore, much less CPUs.
You're proposing putting an entire PC on a PCI card (since it's now gotta have RAM -- which requires a new BIOS
Re:External HyperTransport? (Score:2)
I seem to remember somebody selling "system extenders on a card" back in the late '80s or mid '90s - that fad may have come 'n gone more than once. I also seem to remember the benchmarking showing that the pathetically sad system speed was due to memory latency issues...
Re:External HyperTransport? (Score:2)
You're right that we'll have faster architectures in the future that will make this obsolete/limited, but if it gives more raw processor cycles in the meantime, then some people will find it useful - though likely not mainstream g
So the CPU will still be waiting for RAM? (Score:2, Interesting)
Re:So the CPU will still be waiting for RAM? (Score:3, Interesting)
Sure, with it there would be a possibility of cache coherency issues while without there would be a performance hit whenever something hit the bus...
I guess it'd depend on the cost of ram when building such a device... I'm guessing that a whopping 64-128 meg cache aught to be enough for sometime.
Re:So the CPU will still be waiting for RAM? (Score:5, Funny)
Re:So the CPU will still be waiting for RAM? (Score:3, Funny)
The Rain in Spain Falls Mainly... (Score:2)
Re:So the CPU will still be waiting for RAM? (Score:3, Informative)
Re:So the CPU will still be waiting for RAM? (Score:4, Informative)
The other thing that you are describing is multiway branch prediction. A processor like the Pentium guesses which way a branch goes and despatching instructions down that path to the pipeline. When it is wrong there is a hit as the pipeline stalls and all of those cycles are lost. In multiway branching both outcomes of the branch are despatched to the pipeline. The cost is that half the instructions being executed will be thrown away. If you go 2 branches deep then it is 75%. The advantage is the latency is minimised as the pipeline is always full.
The last thing is processor-in-RAM, or smart memory. In this system a miniture processor is embedded on the DRAM die. The small processor is capable of computing striding patterns in arrays. As the program executes on the main processor the smaller processor predicts which memory locations are going to be accessing and presending the data to the host processor, reducing latency.
Good luck on your class. Architecture is one of the more interesting courses in a CS degree.
Re:So the CPU will still be waiting for RAM? (Score:2)
Re:So the CPU will still be waiting for RAM? (Score:2)
I dunno, given that this will be useful for embedded applications I'd say it's your firmware that's in question.
Re:So the CPU will still be waiting for RAM? (Score:2)
Re:So the CPU will still be waiting for RAM? (Score:2)
Re:So the CPU will still be waiting for RAM? (Score:2)
The problem with integrating DRAM is that capacitance is very sensitive to heat; cells won't be able to hold a charge (and will be useless functionally) if temperatures get too high.
Re:So the CPU will still be waiting for RAM? (Score:3, Interesting)
Re:So the CPU will still be waiting for RAM? (Score:2)
Re:So the CPU will still be waiting for RAM? (Score:2)
Re:So the CPU will still be waiting for RAM? (Score:2)
What you are describing is cache (Score:2)
What you describe doesn't really solve any real problems. Graphics cards bennefit from fancy memories like gddr3 because they are bandwidth
Re:So the CPU will still be waiting for RAM? (Score:2)
External FGPA units? (Score:3, Interesting)
This can only be a good thing.
Low boost (Score:2)
Im a great fan of FPGA and they they are cool, but i also know what their place is, and replacing comparably ( relative cost/performance curve ) cheap CPUs isn't it.
A port? (Score:2, Funny)
Is this a serial connection?
Or will you need a foot wide port with 700 or so contacts on it?
I know serial connections are very fast nowadays, but I don't know if you can get the entire memory bandwidth of a cpu without spreading the bandwidth in parallel connections.
Re:A port? (Score:2, Interesting)
IMHO, fiber optics- though delicate, could offer higher bandwidth. I'd rather have my whole fiber go dark from a break and know it than have one strand of many go out and not know it and have all kinds of whacky/intermittant behavior.
I still struggle to understand why fiber optics are so expensive- the lasers used are fairly cheap and the cab
Re:A port? (Score:5, Informative)
Re:A port? (Score:2)
Nice... (Score:2)
Computing might just become fun again. Small systems passing information around to form a display wall, or big systems chained together t
Re:Nice... (Score:3, Interesting)
Just my $0.01
Re:Nice... (Score:2, Troll)
Re:Nice... (Score:3, Insightful)
Re:Nice... (Score:5, Funny)
Hell, I've got some change left over from lunch, I'm thinking of buying SGI.
Re:Nice... (Score:2)
I have an SGI running Linux that has NUMAlink with cache coherency with stock Itanium CPUs and of course NUMAlinks. Is this something that cannot be extended from what SGI has done to use the cache coherency over HTX?
I don't know, but hopefully someone does.
Re:Nice... (Score:2)
Whatever. If you're in IT and you don't invent two words a year you're coasting. Try 'elaborisha': (obviously excessive complexity for the sake of questionable or obsolete tangibles.) Zero hits on Google. Verb it and you have elaborize.
Computing might just become fun again.
It's fun now. Over at Supermicro you have four socket motherboards designed for 1U hosts. Intel is planning 4 core CPUs (MP, blah blah) by Q1 '07. 16 cores in 1U. Meanwhile Sun has an 8 core CPU sh
Hmmmm. (Score:5, Insightful)
Dave has a processor intensive project this week? He gets the big stack plugged into his machine until someone else in the office needs it.
Server getting bogged down? Add another couple modules to the system.
I like the idea.
m-
Re:Hmmmm. (Score:3, Interesting)
Lets say your company has a 4-way hub that can be plugged into the system of choice... imagine the cooling such a thing would require in order to keep from burning up in its enclosed plastic or (more likely) metal box.
Not to mention the noise... oh good god the noise. My dual core 3800+ at home is quite loud... I can only imagine what a few of those bad boys sitting on your desk would sound like under full load.
Re:Hmmmm. (Score:2)
Re:Hmmmm. (Score:2)
Really? I've got a 4200 with the stock cooler and it's whisper quiet. I had a shuttle box before and I was afraid the switch would be unpleasant. (I've had cpu coolers before that sounded like jets taking off. Not good...) But the cooler that came with the cpu was just fine, not much louder than the shuttle, and I run it with an open case.
Re:Hmmmm. (Score:4, Insightful)
No it isn't you dummy, your cooling system is, now just get a knowledgeable friend to slap a Thermalright HR-01 and a Nexus 120mm fan (undervolted to 9V) on it and it'll be whisper-quiet.
Re:Hmmmm. (Score:2)
One of the things that people forget is that one of the biggest reasons that most PC cases are loud is that they have to be upgradable, and re-configurable. By default, the fans are full speed, and the air flow isn't designed for quiet operation.
If something's a sealed module that will never need to be opened, the thermal profile is a known quantity that can be engineered around. Look at Apple's G5 series: whisper quiet, unless your amb
Re:Hmmmm. (Score:2)
No, the one thing people forget about is that they didn't care about noise in the first place, not until they started going deaf, and they didn't want to put $50 into their CPU cooling solution and stuck to the crappy buldozer-engine like 60mm fans because it was
Re:Hmmmm. (Score:2)
The new socket AM2 dual core Athlon X2 3800+ will be available in both "normal" 89W versions and ALSO 65W and 35W (!!) versions. The 89W number is already lower than what the Athlon (original one, not XP) 1400 would require. Simply put, these processors are not power hungry. Furthermore, y
Re:Hmmmm. (Score:2)
I suppose a good deal of issues could be eliminated if low power cpu's were to be used in such a manor...
I only do this because you have written this twice. The word is "manner," not "manor." A manner is a way of acting. A manor is a mansion.
Re:Hmmmm. (Score:2)
Re:Hmmmm. (Score:2)
Indeed. It sounds like a Cell-type Opteron configuration waiting to happen. If AMD manages to pull something like that off, Intel will have to eat dust for a while. For now, though, it's a fun speculation.
Finally! (Score:2)
Brains (Score:2)
Mother Nature knew it all along.
Increased Bandwidth (Score:5, Informative)
NOT anything like USB at all. (Score:5, Insightful)
http://www.hypertransport.org/docs/tech/ht30pres.
Re:NOT anything like USB at all. (Score:5, Funny)
Oh, so it's like USB
Re:NOT anything like USB at all. (Score:2)
Well, I suppose so... if you really want to make an SMP box out of low bandwidth, high latency USB links...
Re:NOT anything like USB at all. (Score:4, Insightful)
Re:NOT anything like USB at all. (Score:2)
In the meantime... (Score:5, Interesting)
Most of the HyperTransport updates look to be good (and, frankly, about time) but I am highly concerned that if certain manufacturers (such as Broadcom) haven't even bothered to do better than a fragmentary 1.x and have ignored 2.x entirely, there is little hope that they'll do much with 3.x.
And that's the big problem. If AMD are the only ones who ever implement the specification in full, correctly, then it doesn't offer any significant advantage. It isn't universal enough to be useful. That is the killer that has murdered so many excellent technologies. Being good - even being the best - isn't enough. If a rival is more widely adopted, then it'll be the rival that wins. The marketplace doesn't reward quality, it rewards popularity. Quality achieves nothing.
Broadcom isn't the whole industry: (Score:3, Interesting)
Re:Broadcom isn't the whole industry: (Score:2)
Re:Broadcom isn't the whole industry: (Score:2)
Thanks for the link.
This upgrade to HTX is welcome, and "A good thing(TM)". I posted about it earlier today before hearing about 3.0 coming out here http://it.slashdot.org/comments.pl?sid=183891&cid
It was ignored from moderation, but I thought it was a good post, if I say so myself
Re:In the meantime... (Score:2)
Most of the problems I get with a computer are with those that use chipsets of a different brand as the processor, generally the low end ones though, because I've had very good experiences with a system that had a Serverworks brand chipset.
Just avoid Broadcom (Score:3, Interesting)
Instead of the harping on the implementation (which was done in a slapdash, amatuerish fashion by SiByte in order to make a quick buck - and screw the customer), you should blast Broadcom for basically
Thanks alot (Score:3, Funny)
hehe external CPU, someone got a better batch of something than i did.....
Re:Thanks alot (Score:2)
HyperAmps (Score:2)
So finally (Score:2, Funny)
Re:So finally (Score:2)
We'll be able to go from New York to Tokyo in less than three hours?
Ninety minutes from New York to Paris, well by '76 we'll be A-OK...
Hypertransport is the wave of the future. (Score:5, Informative)
The MacBook Pro sports a 666Mhz DDR FSB, while the Powerbook sports a 133Mhz FSB. It doesn't matter how fast your processor is if you don't have a fast enough way to power it (much like a V-12 will not do well with a single-barrel carb used on a lawnmower engine).
The Von Neumann bottleneck [wikipedia.org] is the significant limiting factor in all machines, once your working set of data exceeds that of your L1/L2 cache. Suddenly your 1.5 Ghz G4 is 266 Mhz
Faster hypertransport means happier users of AMD machines. My AMD64 beats the pants off my Sempron 2500 because its 800Mhz HT bus allows it to do context switches in less than 1/3rd the time of the Sempron!
or... (Score:3, Informative)
Many people (including yourself it seems) misunderstand HT. It isn't the FSB, an Athlon 64 has no FSB. HT is only used to communicate non-memory I/O and to synchronize caches between processors when doing memory I/O. So it's rather unlikely that HT could make your context switches 3X faster. Best thing for that would be a bigger cache, which your AMD64 probably ha
I understand quite well. (Score:2, Informative)
The AMD64 average context switch latency is a few microseconds; 15ns average. Sempron is 10ns best, 70ns average. I can send you a PDF with a few hundred graphs I did with lmbench on several platforms for a reseach project recently, if you don't believe me.
So, if my kernel is doing a context switch HZ times a second, I'
Re:I understand quite well. (Score:4, Informative)
This is wrong. Athlon64s have an on-die memory controller. They communicate with memory directly through the dual-DDR memory bus, no intermediaries. This is what gives Athlons their famously low memory latency.
In Athlon64s, the northbridge as we know it does not exist because the memory is connected directly to the CPU itself. The CPU is connected to the chipset by way of a hypertransport bus, and memory I/O for other devices goes over this bus to the CPU's memory controller.
Re:I understand quite well. (Score:2)
Well, whoever marked you as informative was fooled by the same info that fooled you into thinking this. Hypertransport, as the poster you are replying to explained, is *only* used to acces non-memory I/O in single-CPU systems. In those systems, like yours, it is used as a link between the CPU and the northbridge (as the wikipedia article indicates), but, unlike Intel systems, the R
After taking some time to review direct connect.. (Score:2)
Thanks for the reminder.
Re:Hypertransport is the wave of the future. (Score:2)
Said before and said again... (Score:3, Insightful)
Hey Intel, hows the FSB? And, for that matter, how's that DRM-soaked Viiv product going?
It runs Hypercard like nobody's business (Score:2)
It's smokin!
Re:It runs Hypercard like nobody's business (Score:2)
External CPU? (Score:2)
I'd rather have an external motherboard. Keep the CPU in the case, and everything else outside.
Legos (Score:3, Funny)
The bonus feature would be collecting enough hardware to make the Millenium Falcon out of your PC.
Apple (Score:2)
Re:Apple (Score:2)
And who knows, maybe they'll convince Intel into using HT instead of the CSI bus they've been working on for so long. Intel's got to have an in-house implementation of HT up and running (it's an open standard, why not?), it's not all that far-
Too Thick to RTFA, But A Question... (Score:2)
Or is that completely wrong?
Re:f*** (Score:2, Funny)
I really can't see it being that kind of socket!
For now why dont you just stick with your 'Current Solution' and stop dreaming that you need all that extra 'Bandwidth'
Re:f*** (Score:5, Funny)
Oh I dunno, take it out to dinner, buy it a few drinks, you never know what could happen.
Re:f*** (Score:2, Interesting)
Re:x86 processors (Score:2, Interesting)
And before anyone goes to say NTFS has had those features for years , if that was really true then why can i easily delete files on any windows machine. Why is it that malware can hide in any system directory? because MSFT never enforced those standards.
Re:x86 processors (Score:4, Insightful)
Re:x86 processors (Score:2, Insightful)
But seriously, you got it wrong. It's puke green, of course.
Re:x86 processors (Score:2)
Ouch, that hurt, Andrzej.
Re:x86 processors (Score:4, Interesting)
Re:x86 processors (Score:2)
The x86 came out when disco was still cool.
usually pretty far ahead in tricks to make the x86 ISA fast
going on 30 years of hacking and PhDing the chip will do something.
I've been ready for x86 to die for years now, but then Apple joined the club.
Re:x86 processors (Score:5, Informative)
Re:x86 processors (Score:2)
Re:x86 processors (Score:3, Informative)
Cray use Hyper Transport now
Re:x86 processors (Score:2)
Re:not USB (Score:2)
Obviously we need BadAnalogyGuy [slashdot.org] to comment on this one.
Re:not USB (Score:2)
Re:not USB (Score:3, Interesting)
Re:not USB (Score:2)
Ah. But that's a different HT bus than the one th
Re:not USB (Score:2)
Re:RAM over HT link? (Score:2)
Adding a layer like HyperTransport on top of the direct connections present in current AMD systems would just make things slower.