The Definitive Dual Processor (crap, Dual Core) Definition

[840quadra]

I call for the recognition that "processor" and "core" are interchangeable, should be accepted as such in discussion, and people who say Mac minis are dual processor and Mac Pros are quad processor should not be "corrected" because they are, after all, correct.

I am with you here, I am not one that will jump in and correct someone if they use either of the terms. I only correct when people get confused and think that the G5 Quad, or Mac Pro Quad have a single chip with 4 cores.


Something else to throw in

On the definition of being on the same board. Remember that the Dual processor G4 systems had 2 processors on one board as well. However, they were each single core G4 processors that shared the same daughtercard. I have seen people become confused in the past, calling G4 Duals, the first dual core processor mac, which isn't true.

 

[Cromulent]

I agree that multiple definitions are correct. But I disagree with your "understanding" opinioin. If i tell my friends "well this is a dual processor, four core system" they have no idea what the heck I'm talking about, and it takes further explaining and just overall sounds much less simple (and much less impressive) to say "this has four processors" - which it does.

Basically, we (together) need to right now come up with a concrete definition of what the difference between dual-core and dual-processor actually is, and for that matter if there even is one.

I call for the recognition that "processor" and "core" are interchangeable, should be accepted as such in discussion, and people who say Mac minis are dual processor and Mac Pros are quad processor should not be "corrected" because they are, after all, correct.

Actually that would be wrong. A processor (or more technically accurate a CPU) is the chip itself. It can have 1 core / 2 cores / 10,000 cores is does not matter it is still one CPU.

A Mac Mini has 1 CPU and two cores. A Mac Pro on the other hand has 2 CPUs and 4 cores and should be referred to as a duel processor duel core system.

The reason they are called cores and not processors is because they must share resources with the other cores (cache, bus etc) and that limits there effectiveness. If you could split a duel core processor into the two separate cores and put them on different buses it would perform better than the original duel core. Of course you would have to bear in mind that there would have to be some architectural changes to get it to work.

For this reason alone it is both misleading and wrong to refer to a Mac Mini as a duel processor computer as it only has 1 CPU.

 

[dpaanlka]

I am with you here, I am not one that will jump in and correct someone if they use either of the terms. I only correct when people get confused and think that the G5 Quad, or Mac Pro Quad have a single chip with 4 cores.

And to further my thoughts...

The phrase "Dual Core Processor" itself doesn't make any sense. It should be "Dual Core Processing System" or "Dual Core Unit" - because you can't have a single processor that is two cores - each core is a processor! They work together via various interfacing methods, but they are two distinct processors.

A weird analogy I just thought of - if you have a shirt with two stains, you don't say "I have a two-stain stain" - each stain is an individual stain, existing together via the shirt (the "system").

 

[bearbo]

Actually that would be wrong. A processor (or more technically accurate a CPU) is the chip itself. It can have 1 core / 2 cores / 10,000 cores is does not matter it is still one CPU.

A Mac Mini has 1 CPU and two cores. A Mac Pro on the other hand has 2 CPUs and 4 cores and should be referred to as a duel processor duel core system.

The reason they are called cores and not processors is because they must share resources with the other cores (cache, bus etc) and that limits there effectiveness. If you could split a duel core processor into the two separate cores and put them on different buses it would perform better than the original duel core. Of course you would have to bear in mind that there would have to be some architectural changes to get it to work.

For this reason alone it is both misleading and wrong to refer to a Mac Mini as a duel processor computer as it only has 1 CPU.

i'm not gonna comment on this because i know dpaanlka is all over this now (add: and i was right )

...

now to dpaanlka, how would you differentiate then, between 2 core on same chip and 2 core on 2 chips?

 

[dpaanlka]

The reason they are called cores and not processors is because they must share resources with the other cores (cache, bus etc) and that limits there effectiveness.

Didn't I just disprove that with the "dual-processor" Power Macintosh 9600 example? Also, there are lots of computers in the past that shared their busses with other things (the Mac LC, the Power Macintosh 5200, my old Compaq Presario) and plenty of systems that didn't even have cache. Since when is cache part of the definition of what a processor is?

EDIT: In case you didn't see that - the "dual processor" Power Macintosh 9500 and 9600 systems each had two PowerPC 604 processors soldered onto a single board that shared the same single bus, and a single, external L2 cache.

Besides, there were other "multi processor" systems from various manufacturers before all this "core" nonsense - I'm sure there are other examples of a similar setup.

i'm not gonna comment on this because i know dpaanlka is all over this now (add: and i was right )

You know me well!

now to dpaanlka, how would you differentiate then, between 2 core on same chip and 2 core on 2 chips?

I would say a single chip with two cores/processors should be identified as a "Dual-Processor System," or "Dual-Core Chip," or something like that... but saying a single "processor" has two "cores" would be an oxymoron or whatever the term is.

"CPU" stands for "Central Processing Unit", does it not? It is not (but often misused as) an acronym for "processor" - because "processing unit" does not specify how many processors are there.

So, "Dual Core CPU" would also be correct. But it still has two processors. The "unit" in CPU (coming from "unify") suggests that there could be even two or more individual processors/cores, working together in unity.

 

[Cromulent]

Didn't I just disprove that with the "dual-processor" Power Macintosh 9600 example? Also, there are lots of computers in the past that shared their busses with other things (the Mac LC, the Power Macintosh 5200, my old Compaq Presario) and plenty of systems that didn't even have cache. Since when is cache part of the definition of what a processor is?

Using your logic then all computers with an integrated FPU are duel core systems. That is patently false. We are mearly talking about the CPU here. 1 physical chip inside your computer = 1 processor. Now the Power Mac 9600 may have been different and to be fair it was released before the need for a real definition existed.

Definition :

A dual-core CPU combines two independent processors and their respective caches and cache controllers onto a single silicon chip, or integrated circuit. IBM's POWER4 was the first microprocessor to incorporate 2-cores on a single die. Various dual-core CPUs are being developed by companies such as Motorola, Intel and AMD, and are scheduled to appear in consumer products in 2005.

This is why the terms are not interchangeable. If the Power Mac 9600 was marketed as a duel processor computer then that was before the term duel core was coined. I have no real knowledge about that computer though. If memory serves it used a daughter card to take the second CPU. Correct me if I am wrong, it has been a while since that computer was in the mainstream.

 

[iMeowbot]

"CPU" stands for "Central Processing Unit", does it not?

It does.

It is not (but often misused as) an acronym for "processor" - because "processing unit" does not specify how many processors are there.

Yes, it does: one. A CPU is made up of an ALU, control unit, registers. (this used to be intro to computers type stuff, don't they teach it any more?) Once upon a time the memory was also included, but that went away when CPUs started sharing core (when "core" meant a kind of memory).

So, "Dual Core CPU" would also be correct.

That would be a dual CPU CPU

 

[dpaanlka]

Using your logic then all computers with an integrated FPU are duel core systems. That is patently false.

Well, technically, it would be. And the Quadra 840av would have two processors too - a normal 68040 and the Digital Signal Processor. Although I wouldn't call that dual processor either - because one processor is for general computing use, while the other is very specific (as FPU is). So I shall now amend my definition to pertain only to the "general computing use" category.

A dual-core CPU combines two independent processors and their respective caches and cache controllers onto a single silicon chip, or integrated circuit.

What? How does that disprove what I am saying? If anything that is only further proof.

If memory serves it used a daughter card to take the second CPU. Correct me if I am wrong, it has been a while since that computer was in the mainstream.

No, both processors were physically on the same daughtercard.

Also, I see that each of my Xeon cores features it's own 32kb L1 cache - which suggests that they have some (even the slightest) level of independent cache management of their own. I think that further qualifies them as two processors.

 

[Cromulent]

What? How does that disprove what I am saying? If anything that is only further proof.

It proves it by saying that a Mac Mini is a duel core system and NOT a duel processor system. That is the difference. There is a distinction that must be made, it is wrong to call the Mini a duel processor system.

 

[dpaanlka]

It proves it by saying that a Mac Mini is a duel core system and NOT a duel processor system. That is the difference. There is a distinction that must be made, it is wrong to call the Mini a duel processor system.

How does that sentence prove that? I think it says quite clearly there are two independent processors.

 

[Cromulent]

How does that sentence prove that? I think it says quite clearly there are two independent processors.

On the same chip or integrated circuit. That is the important part.

 

[dpaanlka]

On the same chip or integrated circuit. That is the important part.

But you're ignoring the fact that it says two independent processors. So if someone's Mac mini has "dual cores" which, by that definition, means two independent processors - then how does it not have two independent processors?

Also, it's not "duel" - they're not fighting. "Dual" is the right word, which means two.

 

[iMeowbot]

On the same chip or integrated circuit. That is the important part.

See, that's not important at all. See this thing?

That's a CPU. The memory is on separate boards. The number of chips is totally irrelevant.

 

[Cromulent]

But you're ignoring the fact that it says two independent processors. So if someone's Mac mini has "dual cores" which, by that definition, means two independent processors - then how does it not have two independent processors?

Look the definition was fairly concise. If you have two separate processors on two different chips it is a dual processor system. If they are combined on the same chip they are a dual core system.

Also, it's not "duel" - they're not fighting. "Dual" is the right word, which means two.

Thank you for that.

 

[Cromulent]

See, that's not important at all. See this thing?
View attachment 65273
That's a CPU. The memory is on separate boards. The number of chips is totally irrelevant.

Did you even read the definition I posted above?

 

[dpaanlka]

Look the definition was fairly concise. If you have two separate processors on two different chips it is a dual processor system. If they are combined on the same chip they are a dual core system.

Well that just doesn't make any sense. There are still two processors in both cases. I'm aware of what the "dual core" phrase being thrown around today means - the whole point of this thread is to question the very reason it exists (because it doesn't seem to have one).

 

[Cromulent]

Well that just doesn't make any sense. There are still two processors in both cases.

Two processors in both cases, yes. Two processors and two chips in both cases? No.

 

[dpaanlka]

Two processors in both cases, yes. Two processors and two chips in both cases? No.

Who said anything about chips!??!

Why can you not say there are two processors if the friggin' computer has two processors (as you just said)???

 

[iMeowbot]

Did you even read the definition I posted above?

You wrote:

Actually that would be wrong. A processor (or more technically accurate a CPU) is the chip itself. It can have 1 core / 2 cores / 10,000 cores is does not matter it is still one CPU.

A Mac Mini has 1 CPU and two cores. A Mac Pro on the other hand has 2 CPUs and 4 cores and should be referred to as a duel processor duel core system.

And that's nonsense.

A CPU can be made of many components. With integration, many CPUs can be placed on one component. The number of discrete parts does not matter.

 

[Cromulent]

Who said anything about chips!??!

Why can you not say there are two processors if the friggin' computer has two processors (as you just said)???

Because the definition (the whole point of this thread I thought) was that a computer with two processors on the same chip was a dual core system.

 

[dpaanlka]

Because the definition (the whole point of this thread I thought) was that a computer with two processors on the same chip was a dual core system.

But that definition is true. It also would be correct to say two processors. It has two processors. It has two cores. Neither statement is false.

I want to bring to light how ridiculous it is to tell people their dual core systems do not have two processors.

Also, a computer with two entirely independent processors that do not share anything (like previous dual G5s) still has dual cores.

 

[Cromulent]

But that definition is true. It also would be correct to say two processors. It has two processors. It has two cores. Neither statement is false.

I want to bring to light how ridiculous it is to tell people their dual core systems do not have two processors.

Well what is the point of having a definition if you are just going to ignore it? That would be a dual core system. It is down to the people being told to understand what a dual core system is.

You can not just pick and choose what you want to call something because it does not fit in with what you think it should be called.

 

[Cromulent]

Also, a computer with two entirely independent processors that do not share anything (like previous dual G5s) still has dual cores.

Oh come on, can you not see how you are just squirming around this issue? The definition was clear a dual core system is a computer with two processors on the same chip. A system with processors on separate chips would be a dual processor system.

Maybe they should rename dual processor systems to something like independent dual processor system to make it clear so that people don't get all pedantic about definitions.

 

[dpaanlka]

Well what is the point of having a definition if you are just going to ignore it? That would be a dual core system. It is down to the people being told to understand what a dual core system is.

You can not just pick and choose what you want to call something because it does not fit in with what you think it should be called.

Sure you can. I have a monitor and a display on my desk, but I only have one thing.

The point is, these "dual core" Macs have both two processors and two cores. Old dual processor Macs also have two cores. You can say either one, but I honestly would just rather stick to "dual processor" or "quad processor" - because I'm sure most people in the world still do not know what a core is and how it relates to processors.

Oh come on, can you not see how you are just squirming around this issue? The definition was clear a dual core system is a computer with two processors on the same chip. A system with processors on separate chips would be a dual processor system.

Are you like, ignoring everything in this thread? No matter if there are two processors on the same chip or on twenty chips, they're still two processors. Nothing is changing the fact that there are two processors. How can you possibly tell me you do not understand this?

How does it go from having two processors to one processor when there are clearly two? Simply soldering them together?

 

[gnasher729]

I see that some people who call their Macs "dual processor" or "quad processor" systems being shot down and corrected now and then. "It's COREs, not processors." But is not a "dual core" basically just two processors on the same board sharing the same cache and bus?

There are different definitions around what a "processor" is. Especially IBM and Intel have been in disagreement quite often. So some people would say the for example a current (Jan. 2007) iMac has one processor, others would say it's two processors. You try to get them to agree.

They will all agree that it is two cores. When it is important, I would say it is one chip with two cores and avoid the word "processor" (for example, at some point Apple might build a one chip / four core MacPro instead of the current two chip / four core ones). (In Intel/AMD speak, the word "socket" is often used; I don't like it because again Apple could build a MacPro with two sockets, of which one is empty).