Dual Core Processing: Over-simplified, demystified and explained.
To SMP or not to SMP?
The processor engineers have probably already thought about tackling the SMP situation. What good is a dual core processor if the software only recognizes and then uses only one of the cores? The majority of software is not written to utilize multithreading at present. This breaks open a whole new can of worms in concepts of parallel computing.
Intel’s Hyper-Threading is a single processor logical variation of dual core processors. AMD has just taken it one step further with two physical cores on one processor die. Could AMD’s engineers have cracked the hardware problem of a dual core processor and load balancing a program that isn’t written for multithreading?
This is where dual core processors could fall short of expectations for mainstream users. If the software cannot “see” the second processor then it will not benefit from it. Programs, such as Adobe Photoshop, are SMP aware and are much faster on a dual processor system. There is no doubt that a program like Photoshop will be much faster on a dual core system than its single core counterpart. The majority of operating systems do recognize and support at least two processors. There is some load balancing of non-SMP applications but not as efficiently as those written for multithreading.
The bottom line…for now
The benefit will come for users who multitask. As in a dual processor system there is a second processor core to share the load either in balanced form or by itself. If one processor is busy burning a DVD then the second is available to, I don’t know, bake bread. The point is there are now two pairs of processor hands to execute multiple tasks simultaneously.
For the home enthusiast it mean less processor hiccups while playing DOOM III and, at the same time, burning a DVD or listening to music.
Dual core processors brings a whole new twist to server environments. Dual or quad servers based on the 940-pin Opteron processor may be on the road to some staggering performance results. AMD recently demonstrated a 4-socket HP ProLiant DL585 server powered by 4 dual core Opteron processors. Think about it. That’s like 8 processors for the price of four. It boggles the mind to think of dual core on an 8-way system.
For the processor manufacturer dual core means a less expensive route to producing a new product that continues the performance curve. The PR Rating numbers will be interesting. A dual core Opteron that has two 2.4 GHz cores won’t be classified as a 3800+, for example, or twice that at a 7600+. Since AMD dual core processors are going to be released in the 940-pin flavor first then it will be an FX. Most likely the FX-57 which brings up the question of “where’d FX-55 go?”
Nevertheless there will be the performance increase and getting the consumers head wrapped around dual core as better will be a challenge. The public believes that two processors are better than one but also expensive. There are two processors (or more) to buy, a multi-processor motherboard, special RAM and so on. With dual core processor technology there isn’t the added cost of a second physical processor. The manufacturing process is very close to single core cost so, it is hoped, that the dual core processor won’t have a shocking sticker price. It will, obviously, be more as the newest and fastest always does cost more but it has to be less than the total of two comparable Opteron processors.
Dual core processors will also be hard to slot into the gigahertz realm of public comprehension. Does “Two 2.4 GHz cores” sound slower or faster than the same processor described as a “3.6 GHz comparable”? It’s for certain that the two core clock speeds won’t be combined for a gigahertz rating but a comparable gigahertz rating will be assigned for those still stuck comparing which number is bigger in the gigahertz wars.
Bottom line it’s what we’ve been saying for a year now. It’s the mushroom effect. For AMD it isn’t so much about do it faster….it’s about do more of it faster.
AMD must be feeling smug by now because many had foretold of the end of the 940-pin era for the desktop and workstation. Opteron indeed is alive and well for the server but it will again be heard roaring in the enthusiast and desktop market.
More on AMD and dual-core processors at the AMD website.
gimme gimme gimme
MediaMan, i would like to give my most sincere thanks for an absolutely fantastic article. Me and a few of my friends here at Shell ( UK ) are really interested in the upcoming dual core technology. The difference between you and other reviewers is that you explained things so smoothly.
Many thanks.
James.
I love the gimme icon
James,
Thank you for the comment. I hope you keep poking about our site.
Interpreting the crystal ball on this technology is one part science and one part darts. My crystal ball sees dual core as indeed a performance increase. That's a given with any new processor product at the top of its line.
When you look at it from a consumer cost point of view it begins to make a bit of sense. It's ideal for workstation users who have a desire for a bit more "horsepower" than a single processor system but don't have/want to spend more $ for a dual processor system.
Dual core brings some of the benefits of a dual processor system at less than the cost of a 2P system with the two of the same processor equivalents.
Remember that it's not so much about flat out dragstrip speed anymore. A dragster isn't much good at towing your boat down the highway. It's more about having that big truck with the towing power...that can keep up with the dragster or at least give it a good run for its money.
For server environments it's the same way of thinking. Many run dual processor servers but would really like a 4P server to really go to town. But then there's that cost factor. A dual core system can bump them up between a 2P and 4P system for some aspects of performance (increased multitasking) but without that cost.
For those with oodles of money? Imagine a 4P or an 8P system with dual core processors...that would translate up to a psuedo 8P or 16P system. Interesting if anyone tries to make an 8P dual core system actually work...just for the heck of it.
Bottom line dual core isn't exactly the same as a two physical processor system but it's better at some things than a single processor system. On launch this is more a product for working rather than playing...
In time...it'll become more affordable for us enthusiasts then we'll play too!
WOW MediaMan... Great article. Clear and very well written.
Good article, but one thing: In AMD's Dual Core implementation the cores are NOT linked together using HyperTransport. They uses a more direct coupling called SRQ (System Request Queue). The advantage is that cache coherencey updates between the cores are much faster. I.e. AMD's dual core implementation is no different to it's single core cousin with respect to HyperTransport/crossbar/memory-controller. Of course Hypertransport-Links can be used to extend the system with further CPUs, but that is a differnent story.
Good article! The best is that it explains things in a way that you don't need to be an engineer or a mathematic professor to understand most of it
I usually understand most of more advanced articles, but why make it more complicated then necesary?
I wouldn't be to suprised if AMD releases dualcore versions of their Opteron 1XX, Opteron 2XX and Opteron 8XX CPU,s in 2005 and not just for the heck of it. A system with 8 dualcore Opteron 8XX CPU's would ofcourse be 16 cores in total.
But I don't think Socket940 will be big in the enthusiast market. Sure some will ofcourse get it, just like there are allready some enthusiasts that have Dual Pentium III/Athlon MP/Xeon/Opteron systems. But I think most enthusiast will get dual core Socket939 Athlons, that probobly will be released in late 2005.
Some may want/need ECC memory and get Socket940 instead or need more then one dualcore processor for the specialized personal use, but I think the Socket939 platform will be more popular.
The one who lives will see.
Some may want/need ECC memory and get Socket940 instead or need more then one dualcore processor for the specialized personal use, but I think the Socket939 platform will be more popular.
Funny thing about enthusiasts...we all look for the best deal and sometimes whine about the high cost...but tally up what we actually spend on the entire box. It'll be much more than the average user. We're funny that way.
You are on target that Socket 940 will not be as popular with the enthusiast. Socket 940 wasn't designed for the enthusiast really. Socket 939 is better suited first and foremost because of its ability to use "normal" memory rather than the more expensive REG ECC.
Think of Socket 940 more for the performance workstation. It's a lot of horsepower with the benefits that pertain to ECC REG memory.
By coming out with a BIG impressive Socket 940 FX processor...it grabs the headlines. It says "Hey...look at AMD!". Then AMD can follow up with other products once they have the attention of the readers.
It's the same philosophy as having a loss leader item on sale at a store. The loss leader item brings shoppers in. Very few of them may purchase it but they are in the store...they'll most likely pick up other things while they are there.
Funny thing about enthusiasts...we all look for the best deal and sometimes whine about the high cost...but tally up what we actually spend on the entire box. It'll be much more than the average user. We're funny that way.
Yes, it's not getting from A to B that mathers, it's how much fun you had getting there that counts :P
That statement works somewhat better when you look at cars and motorcycles then computers, but computers can be fun to
By coming out with a BIG impressive Socket 940 FX processor...it grabs the headlines. It says "Hey...look at AMD!". Then AMD can follow up with other products once they have the attention of the readers.
Yes, AMD allready do Socket939 version of Athlon 64 FX though. But a Opteron 2XX system will still be nice. If you get that when dualcore gets out that means 4 cores instead, not to shabby
MediaMan, great work man.
I've just finished my English homework, we were supposed to find an interesting article and write a summary of it, and of course, I chose this yours.
Keep up the good work.
/SpinBoy
I think you should title your page, AMD Hype.
Or not, because AMD announced dual-core CPUs first, and that's what the article is based on.
Acid-
I believe that this is one of the best non-biased articles I have ever read pertaining to processor technology. Bravo.
MediaMan, I think you missed your calling. You should have been a school teacher. With a article that well written even the class clowns would get an "A" on their exam....bloody good m8..
IBM have had a dual core server chip out for years, so saying that AMD engineers have "cracked" anything is perhaps innaccurate, all they have done is brought the option of a dual core cpu down to the pc level.
And thats what matters to us now isnt it.
I don't understand how an app (e.g. Photoshop) could take advantage of an SMP. I mean, doesn't the OS "shield" the hardware from the apps? Applicantions are not supposed to know about whether it is a uniprocessor, an SMP, or a dual-core, right? And what if the app knows it's SMP or dual-core, but the OS doesn't support SMP or dual core? Is it possible? Thx.
sorry that i have to make a comment about 64 bit processors here, because there is no 'comment' feature in the "64-bit simplified" article.
What on earth is a 64-bit processor? Does it mean 64-bit data bus? 64-bit control bus? 64-bit registers? 64-bit everything?
I don't understand how an app (e.g. Photoshop) could take advantage of an SMP. I mean, doesn't the OS "shield" the hardware from the apps? Applicantions are not supposed to know about whether it is a uniprocessor, an SMP, or a dual-core, right? And what if the app knows it's SMP or dual-core, but the OS doesn't support SMP or dual core? Is it possible? Thx.
The OS doesn't do any more shielding from apps these days than buffer overflow protection with the NX/EDB bits on Intel/AMD processors. Applications, the OS, and the hardware is designed to let the application know if SMP exists explicitly for the purpose of taking advantage of it. Applications are most certainly supposed to know. Additionally, if the OS doesn't support SMP, the application has no idea -- it's all fed directly from the OS.
sorry that i have to make a comment about 64 bit processors here, because there is no 'comment' feature in the "64-bit simplified" article.
What on earth is a 64-bit processor? Does it mean 64-bit data bus? 64-bit control bus? 64-bit registers? 64-bit everything?
In computers, a 64-bit processor is one in which data is processed and/or stored in 64-bit chunks. The term often refers to the size of the CPU's registers that holds memory adddresses and other data, as well as the arithmetic logic unit that operates on those registers to compute. Busses have been varying widths for ages, with the Athlon XP being a 32 bit CPU with a 64 bit bus (Twin 32 bit pipelines) -- the Athlon 64 has a 64 bit memory-to-CPU bus, and a hypertransport bus which is CPU-to-chipset and it's 16bit bi-directional. A computer architecture described as "64-bit" generally has integer registers that are 64 bits wide and thus directly supports dealing both internally and externally with 64-bit "chunks" of data.
Bus widths don't count in the equation.
if more info needed i will register
Nice article, very informative.
gimme gimme gimme !!!
Great article, Thanks!
I do have a question ! Will these processers be more ESD sensitive that
the commonly used ?? Will special precautions have to be taken ?
JG
For those who may not understand the previous poster's question;
ESD = Electro Static Discharge.
ESD is a term most commonly used when handling/transporting electronic equipment such as microprocessors. I would imagine that the dual core processor would be handled with the same precautions as a single core processor. The ESD risk would be the same.
Excellent! Excellent! Excellent!
Thanks
Wow this came out of the wood works...
Thank you so much for putting together such a great article. This is the best explanation I ever got about the dual-core technology so far, and, finally, I start to understand how things work.
thanks man
i learnt a lot!
thanx
Awesome breakdown!
Quick question:
I saw some computers advertised on ebay with intel core duo procs. The seller claimed the the Ghz rating applied to each core, making a dual-core 2.0Ghz chip actually clock at a total speed of 4Ghz all together.
Is this anywhere near true? Seems oversimplified to me.
It's not true. The cpu still clocks at 2ghz. The seller is using pseudoscientific fakery to make the thing sound better than it is. That is not to say that a dual core 2.0ghz is a slouch. It is a cutting edge machine. The seller should be more honest - that thing could sell itself without relying on that kind of bullcrap.