Dual Core Sucks at Multi-Tasking

ok so you hear all the time how people can run a virus scan and play a game without losing FPS or bog-down so i tested this without any scan its like 50-60fps Counterstrike 1.6 so i ran an Nod32 virus scan and then played and its unplayable with chopyness and bounces from 7-50fps eratically and is pretty much rendered useless to play witho0ut being killed because of it. hmm whats this about i even tried setting my cpu to max performance instead of dynamic switching (NHC) and i have 2gb of ram!! what gives hmm

 

128MB Nvidia GO 7200, this maybe ur bottleneck, not the CPU.

 

Yes it most certainly is your GPU which is holding back from the other components.

 

Wow, I'd like to buy some punctuation... Just the occasional comma would make your post *much* easier to read...

Anyway, I'd recommend trying to run a virus scan while gaming on a singlecore machine, if you think it's bad on a dualcore system.

The thing is that yes, you have two CPU cores, but 1) You don't have any guarantee that the game will get a core to itself (if the virusscanner runs multithreaded, it will itself try to take advantage of both cores, so competing with the game for resources), and 2) You only have two CPU cores. Everything else is still shared. If both programs need a lot of RAM access, that might become a bottleneck. If they both require HD access, that might become a bottleneck.

 

Its your GPU, it can also be your HDD being in heavy constant use while the virus scanner does its thing.

But the CPU itself is NOT the bottleneck.

 

Earlier I was installing F.E.A.R. Combat, burning a back-up of it in Nero, surfing the web, and acting as a SEED in Azureus with no slowdowns whatsoever.

 

Why would the GPU be affected by a virus scan in the background?
The CPU can easily be a bottleneck. If the virus scan is capable of using both cores.

 

I meant the game was using up all the GPU's resources, the 128mb 7200go is not a good card.

And then the HDD was probably being accessed constantly while scanning for viruses.

The CPU could not have been the bottleneck unless it was running at 987mhz because it was unplugged or set to maximum battery mode.

 

Most gamers that I know will actually turn down/off as many applications as possible to enhance their gaming experience by freeing up as much of their computer's resources for the game.

I think that what you've read was that the Core Duo can handle a lot of different applications/operations at once as far as multi-tasking is concerned. Running a virus scan can be very taxing on the system. Besides, you can't really multi-task when being chased around by heavily-armed enemies .

 

No they won't. They can't easily do that, in fact. (Well, it's easy enough to terminate other processes, but the user tends to notice that. But what they can't do is "pause" other apps, except by raising their own priority, which I think I've only ever seen one game do.

But he said performance was particularly affected when running a virus scan in the background. It ran fine otherwise.

Says who?
A virus scan does use a good chunk of CPU. *If* it can run multithreaded, it'll be able ot use a good chunk of CPU on *both* cores. Which could easily become a bottleneck, in the same way that it's a bottleneck if you try to do this trick on a single core system. Now, I have no clue how Nod32 works. Only used it once, years ago, and dualcore systems weren't exactly common back then.

 

Can't you set up up your CPU to dedicate a core to a single application (I don't have dual core myself but I think I've read people doing this)? Perhaps setting up the virus scan to only use one core will stop it running multi threaded if that's what its doing? To be honest though, I think its probably the hard drive causing the bottleneck.

 

You shouldn't have any slow-downs while running a virus scan and playing a game on a Core Duo. I do that as a test on most of the machines I get.

The last laptop I tested had 1GB RAM, 256MB Go7600, and a Core Duo T2500. I ran a full avast scan and played BattleFront 2 at the same time with no slow-downs. I think NOD32 virus may be multithreaded as Jalf said.

 

How would my video card be holding me back when i play it without the scan fine? obviously nod32 doesnt take up my graphics memory So Nod32 being multi-threaded is probably the issue what virus scanners arent so i can test it again and 128MB nvidia will play Counterstrike 1.6 just fine. But doesnt this kind of suck and defy the whole point of multi-core processors i would want it to use 1 core then use the other for the game.

 

As the reason why the Frame Rates wer going up and down may be because he was running the game at high resolutions and detail settings which the GPU may not have been able to handle.

 

Not only that, but Norton is notorious (pun intended) for being a resource hog, in terms of the CPU, HDD, and RAM. You could try another antivirus program and see radically different results. Also, many of the people who make these overblown claims of multi-tasking usually aren't running games at all.

 

What jalf is saying is that the GPU is not hindered by the anti virus, therefore if he was playing with the settings too high, he would get choppy performance in the first place - without the antivirus on - and still get choppy resultswith the antivirus on.

So in escence the problem has nothing to do with the GPU, its down to either the CPU, RAM (les likely) and HDD

 

the game is fine without the virus scan its like 50-60 fps depending on what im doing and if in battle but with scan it just is choppy and erratic fps with nod32 not norton :/

 

First, I assume you do have 2GB memory like your sig says. In that case, we can probably safely conclude that the problem isn't that they're fighting over the same limited memory. 2 gigs should be enough for both game and antivirus...
It is still possible that memory bandwidth might be a problem, though.

It might be. I'm not sure, it was just a guess, but it could explain what you're seeing. In most cases, though, I'd say it being multithreaded is a good thing.
I'll get back to that below

Not really. The point of multi-core processors is to be able to execute multiple threads simultaneously. The CPU doesn't care whether you're running two threads from one process, or running two separate processes. Execution also switches between cores rapidly. By default, Windows doesn't reserve one core for your game, and one for the virus scan. Rather, both cores get assigned a new thread every 1/50'th second or so. When that happens, each core is just assigned the first available thread in the queue. So your game might run on core A for the first 20 ms, then jump to core B for a while, then back to A and so on. And the same goes for the antivirus scan.

Keep in mind that the antivirus scan will be able to finish sooner if it's allowed to use both cores. As such it doesn't defy the point of multi-core processors. It allows a program to take advantage of both cores.

There are two possible solutions. First, you can set the processor affinity on the process, so it sticks to one core only.

Alternatively (and this is probably the best solution), just lower the priority of Nod32. Set it to belownormal or low priority, and it shouldn't interfere with your game.

 

I ran Ad-aware scan and cs.16 and did the same test and it was playable with ocassional drop spike happened like twice in in one round

 

Perhaps it is a network issue - lag spikes, etc. Check your ping.

I don't know if HP properly sets up Windows to run dual-core, but I doubt they do. With the last Core Duo system I tested, I had to configure it so my benchmarks would run properly. For example, in 3DMark06, the CPU score was terrible (around half of what it should have been) - I changed the settings and, lo and behold, problem fixed. Check this out:
http://forum.notebookreview.com/showthread.php?t=60416

 

You're probably right. I was just reporting what I'd read here in a thread about that. I don't think their gains were that much though from doing it.

 

This may be part of the problem: Steam uses 50% of CPU time on Dual Core systems.

A friend's desktop Pentium-D and X1800XL system was having weird frame rate drops in HL2 and CS that were fixed by setting CPU affinity for Steam. Combined with running another CPU intensive program this might be your problem.

 

Oh Steam, Wonderful Steam...

 

There's a reason I won't install that crap on my machine.

 

yeah its the video card thats the bottle neck. For me my ram would cause that as Im using too much ram when scanning and playing at the same time. Now if I had 2gb Id be fine.

 

Let's try this one more time...

He is getting fine framerates when not running an anti virus scan. But when antivirus is running in the background, performance suffers.

How exactly can this be the video card's fault?

 

The card he uses eats into system ram. scanning and playing eats ALOT of ram. That is my guess. Because I have a t2300 1.66ghz and I can game and av scan at the same time (minus bf2 where Im maxed on ram without an av scan).

 

(so what your saying is that it's the RAM and NOT the GPU????)

The GPU Can't be the bottle neck since he gets good results when the AV isn't on.

 

I suppose a task manager screen shot would answer some questions and stop everyone going around in circles... *cough*

 

What Im saying is that since the video card he uses utilizes system ram and now with the game running AND a av scan that he MAY or MAY NOT be eating too much ram. With a combo of of the two at the SAME time.

I NEVER said GPU i said video card as in the combo of GPU and RAM. Obviously the gpu seems to handle it but its VERY possible that the VRAM is the issue.

 

Except that the VRAM isn't relevant. RAM might be, but that's not typically considered part of the video card, even if the video card uses some of it...
And on a system with 2GB RAM, I highly doubt the video card would be able to hog enough memory to make a difference.