How does a dual processor system work?

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rive22

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Hey, I'm going to be getting me a new board, ram, and maybe even a new chip or two. So I'm wondering if anybody can tell me what the point of having a dual processor system is? Or how I can benifit from making a setup like that? How does it work? Is there a screen on my computer that lets my assign each processor to certain tasks or do they work together or what? I don't really get it. Would that double the output? If I got a board and put two 2.4 chips on it, could I still overclock or not really? Even at stock speed, would that board perform better than say a single chipped board that is clocked at 3.6? Thanks :D
 
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Can I have one processor working kazaa or emule at 100% and then have the other one free so I can still use my computer efficiently?
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Yes.
Or what would happen if I were to assign both processors to the kazaa task? Would that double the output?
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Maybe.
If the task was SMP enableabled then yes.
Otherwise no.
But you can run two tasks at the same time.

The advantage of a SMP is that its hard to slow down with work.
So if your doing a lot a multi-tasking then a SMP will do it better.

BUT it only runs a the speed of the one CPU's/ FSB for most games.

SMP's tend to be servers so there are less options to overclock.
But they do tend to be more stable.

Luck........:D
 
This site has a descent explanation of what it is.

to answer some of your quesitons though.

Benefits:
IF and only if the program(s) is/are coded to utilize SMP funcitons such as being multi-threaded, will they benifit from having more than one proccessor available.

What you will see: Better overall system performance while multi-tasking due to the fact that 2 completely programs can be processing at the same time. Program A can be on CPU 1 at the exact time that Program B can be on CPU 2.

In a NON SMP (one CPU) enviornment, Program B would cannot be on the CPU at the exact same time as Program A so it would have to wait for the CPU to tell it that it's Program B's turn.

Misconceptions:
having N number of processors running at X speed does not give you N*X performance.
You ask why -> in the desktop enviornment you are still sharing memory. From the example above, Program A and Program B are both loaded into the same subdivided chunch of RAM. This goes into a big complicated discussion about advantages/disadvantages of using shared memory and each processor having its own dedicated chunck of memory. If you want to learn more about SMP there is plenty of info out there. Another reason is that alot of applications aren't written with SMP directly in mind.

Recap:
You will get better overall performance but the % increase will be completely dependent upon the programs you use and how much you multi-task.
 
Originally posted by FrothyByte
What you will see: Better overall system performance while multi-tasking due to the fact that 2 completely programs can be processing at the same time. Program A can be on CPU 1 at the exact time that Program B can be on CPU 2.
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Well said! :) That is the single most observed benefit of people switching over from a single rig (even with HT) to a real SMP rig (with or without HT).

There is one thing that you can't quantify - 'system responsiveness'. You just can't measure it or use a benchmark to check out against, but it's there all right... ;) It's like the difference between driving a twin-turbo and a simple straight forward turbo engine... They can both achieve the same top speed, but the twin-turbo just 'feel' more powerful. :p
 
No offence, but if you're looking at a computer doing tasks such as using kazaa, I don't quite think you have the needs for an SMP system. I don't know what CPU would hit 100% when trying to use kazaa, maybe like a 200 mhZ celeron or something, but I don't quite think you need dual Xeon/Opteron/Athlons for things like that.

Just my two cents :)
 
Originally posted by RS3RS
No offence, but if you're looking at a computer doing tasks such as using kazaa, I don't quite think you have the needs for an SMP system.
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That's a darn good point!! I didn't see that... Yeah, why you want to build a duallie for kazaa?? :rolleyes: :confused:
 
oh hell yeah, thanks guys that totally rocks! I am a major fan of multitasking by the way. Mostly audio and video stuff like cakewalk, photoshop, dvdx, and premeir. You would be very surprised how fast my processor goes up to 100% and stays there until things settle down a bit. Cool, thanks for the words though for sure everybody. The twin turbo was a VERY good way to put it as well. I think I am going to look more into a SMP rig for my next system. :D
 
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and my two cents: the reason you had 100% utilization from kazaa is the caching and filing work and the fact that its a p4 at 2.4 now what you could do is get more ram and see how the paging relief helps load
 
and my two cents: the reason you had 100% utilization from kazaa is the caching and filing work and the fact that its a p4 at 2.4 now what you could do is get more ram and see how the paging relief helps load
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hmmm, well the cacheing and stuff makes sense, the thing is though i have memzip plus from systweak working with my gig of ram and i have the windows cache set at 600mb for ram ultilization when it needs it, but when my processor is going at 100% when i'm downloading 2,000 pictures my ram meter stays the same, it doesn't use hardly any of that 600 extra megabytes. I have the kernal disabled from being swapped to the swapdisk that way stuff stays in my ram. i do have a pagefile setup though at 1.5gigs on my 7200rpm and stuff gets pushed over into that when my ram hits a low of 32mb left. my L2 cache is 512kb. memzip lets my tweak it to 1024kb, but i dunno if it's really doing it or just making look at so. i could try playing with it more. you said i need more ram, but if it's not using it then how would that help?
 
a software program can't add physical cache its probably referencing a bit of the ( painfully slower ) system ram and every time that has to happen ( several billion times a second ) it slows the crap out of the system and lags the processor

turn that crap off

then do some crap

something other than downloading pr0n
 
Even a single threaded app will have its threads distributed as evenly as possible to both processors.For instance if you play a game and look at the task manager you will clearly see that both processors are in use for that single threaded app. This balancing of the processors will continue as you start and run additional programs no matter if there made as single thread or dual threaded apps....Hence the name Symetrical Multi Processing.

Many people over look this fact and some think 1 procesor is tasked with the program and 1 for the operating system. By default this is incorrect.
 
cool, that helps me out too, thanks for the info man. i always wondered about that. that sounds like a much better way to run things if you ask me. :D
 
Originally posted by diehrd
Even a single threaded app will have its threads distributed as evenly as possible to both processors.For instance if you play a game and look at the task manager you will clearly see that both processors are in use for that single threaded app. This balancing of the processors will continue as you start and run additional programs no matter if there made as single thread or dual threaded apps....Hence the name Symetrical Multi Processing.

Many people over look this fact and some think 1 procesor is tasked with the program and 1 for the operating system. By default this is incorrect.
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Of course, this isn't neccesarily a good thing if there's lots of inter-thread communication, so now and then something might run better if it's constrained to only one processor.
(Or a NUMA-system, I guess, but that's not price effective for a workstation :D )
 
I have a Dual PII system. 100 mhz fsb. It gives a much higher framerate over Remote Desktop than my 1 ghz PIII does. 350 x 2 vs 1 ghz x 1... I'd pick the Dual PII. :p

Dual systems are quite a bit better IMHO compared to single processor units. My dual PII has never locked up once. ;) Even when my two PII 350's were at 391 mhz. :p
 
Originally posted by ’m‚³‚ñ
My dual PII has never locked up once. ;) Even when my two PII 350's were at 391 mhz. :p
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That may have something to do with the operating system(s)... ;)
 
Originally posted by spikegifted
That may have something to do with the operating system(s)... ;)
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:p Windows XP Professional installed on a 1.2 gb disk, with a second 2 gb SCSI drive in it was well. :p
 
ok, i don't mean to sound like a dumb nut, but what's folding?
 
Originally posted by spikegifted
Now, I'm really impressed!! :cool: :)
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It's not particularly functional... No SP1, updates won't install. It's constatntly bitching about low disk space, and I have turned everything down or off.

Hmmm, lowering the paging file size so I can possibly install some updates. :p The PIII has a 1.2 gig drive for Windows. It's a little happier with the other drive as slave with some stuff on it. It's more of a PITA than it's worth IMO. ^_^
 
Originally posted by RS3RS
No offence, but if you're looking at a computer doing tasks such as using kazaa, I don't quite think you have the needs for an SMP system. I don't know what CPU would hit 100% when trying to use kazaa, maybe like a 200 mhZ celeron or something, but I don't quite think you need dual Xeon/Opteron/Athlons for things like that.

Just my two cents :)
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Well, consider all the Spyware your average KaZaA user is running all the time. I could see it using quite a bit of cpu time.
 
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