How many cores are effective for most games?

[geofelt]

It is commonly said that most games can make little use of more than 2-3 cores.
I have been looking for benchmarks to document scaling of performance vs. number of cores.
I have seen few valid results. The are mostly apples to oranges.
Looking at the task manager does not do it.
I became interested in this when playing civ5. It takes a very long time between turns; perhaps 20 seconds.
That is with a i5-4670K @4.1.
Civ5 said it is multithreaded. I doubt that.
The task manager showed all 4 threads at about 23%.
One might have assumed that civ5 could make use of all 4 cores.
But, I think windows is just balancing the load among all the available cores.
I used task manager/process/advanced tab to set affinity of civ5 to cpu-0.
It showed 100$ utilization.
When set to cpu-0, and 1, each thread showed 50%
I would like to see a list developed using good benchmarks that document how many threads make a difference for different games.
You can reduce the number of cores in the bios of most motherboards.
You can also turn off hyperthreading.
If any of you out there have a favorite game would you test to see how sensitive a game is to how many threads.
In the case of civ5, my anecdotal experience shows that it is quite cpu bound and can use only one core effectively.

 

[Lee-m]

4 Strong cores (intel) or 6 weaker ones (amd). Should stay the same going forward too.

 

[geofelt]

4 Strong cores (intel) or 6 weaker ones (amd). Should stay the same going forward too.

I am looking for some links that document that common assertion.

 

[TheRevo]

A lot of newer games try to utilise 4 cores in some environments in the game. So Quad Core is enough for pretty much all games... Dual Cores are probably enough for a large amount of games that are a few years older

 

[geofelt]

Do we have any specifics, testing 1/2/3/4 cores with a specific game that is not gpu limited?

 

[miniminc98]

Even 2 strong cores would do these days.. definitely wouldnt reccomend going with a 2 core build though. like answered before, 4 strong cores(Intel) or 6 weaker cores(AMD

 

[ElMoIsEviL]

DirectX games make use of 1 to 4 cores (usually closer to 2-3 cores in more modern DX-11 titles).The AMD Mantle presentation, by Oxide games, discusses this in detail: http://www.youtube.com/watch?v=QIWyf8Hyjbg

Battlefield 4, for example, uses up to 6 cores under DirectX 11 (AMD FX-6300/6350). The AMD FX-8320/8350s end up exhibiting much of what you described in your original post (windows is just balancing the load among all the available cores).

With Mantle on the way, things will change for the better in this department.

 

[Mousemonkey]

DirectX games make use of 1 to 4 cores (usually closer to 2-3 cores in more modern DX-11 titles).The AMD Mantle presentation, by Oxide games, discusses this in detail: http://www.youtube.com/watch?v=QIWyf8Hyjbg

Battlefield 4, for example, uses up to 6 cores under DirectX 11 (AMD FX-6300/6350). The AMD FX-8320/8350s end up exhibiting much of what you described in your original post (windows is just balancing the load among all the available cores).

With Mantle on the way, things will change for the better in this department.

Looks like someone is falling for the marketing...

 

[minerva330]

This is one of the only articles I know of, test older games...http://www.bit-tech.net/hardware/cpus/2010/07/05/how-many-cpu-cores-do-games-need/1

There are some games that use more than four like BF4 but most only utilize 3-4.

 

[Lee-m]

Its down to the programming not the API.

 

[Lessthannil]

The actual quality of the architecture matters more than the amount of cores.

 

[timchou]

Haswell 2 Core
AMD 4 Core

 

[vmN]

Even 2 strong cores would do these days.. definitely wouldnt reccomend going with a 2 core build though. like answered before, 4 strong cores(Intel) or 6 weaker cores(AMD

So you are saying the 4670k is equal to a fx 6300. You might need to reconsider that.

Its down to the programming not the API.

This is true, the API have little to no impact on how many threads a game use.

 

[Fadi Asem]

Most games right now use less than 4 cores but that is changing right now high-performance games will utilise 8-cores or more in the future because most cpus will be having 8 cores when broadwell comes out.
For mid-low end range games I dont think they will care much about threading there games as they dint need to

 

[vmN]

2 for old games such as Skyrim, 4 for current games, 8 for upcoming games.

Okay now now, the very standard thread-usage for games is 2-3 threads.
We are nowhere close for games to fully utilize 8 threads.

 

[vmN]

2 for old games such as Skyrim, 4 for current games, 8 for upcoming games.

Okay now now, the very standard thread-usage for games is 2-3 threads.
We are nowhere close for games to fully utilize 8 threads.

Mantle use all 8 cores, so we are indeed very close.

>mantle.
The software needs to adapt to mantle, to make it successfully, only a portion have publicly said they would develop with Mantle.
So we are indeed not yet.

 

[vmN]

Bla bla, nay sayers. Get with the times already. BF4 will have Mantle within the month. THAT is fact.

What if it is delayed? As we have before º.º

 

[vmN]

Already debunked by EA and AMD. It's on schedule.

Okay, BF4 is will officially support mantle within this month.
That is 1 game out of ? a thousand?

 

[gamerk316]

Even 2 strong cores would do these days.. definitely wouldnt reccomend going with a 2 core build though. like answered before, 4 strong cores(Intel) or 6 weaker cores(AMD

So you are saying the 4670k is equal to a fx 6300. You might need to reconsider that.

4670k wins head to head 90% of the time. The FX 6000 series competes against high end i3's and low end i5's.

 

[Gaidax]

4 cores is the magic number...

Mantle is like a rainbow unicorn at the moment, even if it gets out, who said it will be actually widely used (if at all) and what the gains on the CPU side will be realistically?

AMD is having an amazing PR team, I mean, they made people think that Kaveri is some sort of second coming of Jesus Christ, while realistically it's the same old steam of shit. So I'd take all their Mantle gospel with a grain of salt until we get real benchmarks done.

 

[vmN]

4 cores is the magic number...

Mantle is like a rainbow unicorn at the moment, even if it gets out, who said it will be actually widely used (if at all) and what the gains on the CPU side will be realistically?

AMD is having an amazing PR team, I mean, they made people think that Kaveri is some sort of second coming of Jesus Christ, while realistically it's the same old steam of shit. So I'd take all their Mantle gospel with a grain of salt until we get real benchmarks done.

I wont suspect more than 10-15% performance increase.
Mantle needs to be much better than the current API, else it would be a massive fail.
Why would people rewrite their code into a new API for 10-15% performance increase?
It would be easier to make their current code more efficient.
Also mantle is only supported by a small margin of the consumers, so they basicly needs to have codes for 2 API's.

So it's a risky move.

 

[Gaidax]

4 cores is the magic number...

Mantle is like a rainbow unicorn at the moment, even if it gets out, who said it will be actually widely used (if at all) and what the gains on the CPU side will be realistically?

AMD is having an amazing PR team, I mean, they made people think that Kaveri is some sort of second coming of Jesus Christ, while realistically it's the same old steam of shit. So I'd take all their Mantle gospel with a grain of salt until we get real benchmarks done.

I wont suspect more than 10-15% performance increase.
Mantle needs to be much better than the current API, else it would be a massive fail.
Why would people rewrite their code into a new API for 10-15% performance increase?
It would be easier to make their current code more efficient.
Also mantle is only supported by a small margin of the consumers, so they basicly needs to have codes for 2 API's.

So it's a risky move.

It's a smart move actually, I think they are trying to make Glide 2.0... Where people would buy their stuff just to enjoy Mantle benefits, but yes in order to be Glide 2.0 it needs to be GOOD.

If it's 10-15% then it's not really worth to mess with for your average studio - I mean look at DICE - they are working on it for ages now and still not got it right, not everyone can afford such time waste.

I think AMD do good actually, they concentrate on where they are good, which is graphics and media and it is probably a way to go in the future. Taking on Intel head on with hardware is not their interest.

 

[geofelt]

So far, I have seen only one try at measuring the effect of one vs. many cores.
Thanks minerva330 for the post:
http://www.bit-tech.net/hardware/cpus/2010/07/05/how-many-cpu-cores-do-games-need/1

From those tests, two cores produces substantially the same fps as does 3-6.
In some, clearly only one is used.

While there is cpu activity on all cores, that does not mean that the game benefits from all of them. It simply means that Windows is spreading out the work of one or two threads across the many available threads.

One game(Dirt2) seems to require 2 or more threads to run.

Stalker is a strange case, using one core near 100%. I suspect the game has code to implement affinity to just one core.

I would love to see some more benchmarks which include some newer games.

The graphics drivers have improved to be able to multi thread more.
What is not clear to me is if the driver processing is more or less cpu consuming than the game mechanics itself.

I would love to see something that would break out that split.

 

[jaguarskx]

The vast majority of games only use 2 cores.

However, that is a very general statement since there are specific games which can make use of more than 2 cores. For example, Skyrim is a pretty popular game that only uses 2 cores. Battlefield 3 and 4 also only use 2 cores in single player campaigns. However, in multiplayer both BF3 and BF4 can make use of more than 2 cores.

Hitman: Absolution is a game that definitely does benefit from a quad core CPU. Crysis 3 uses a minimum of 3 cores and I believe Far Cry 3 can also make use of more than 2 cores.

 

[Lee-m]

Metro last light uses all 4 of my cores. Even on max gfx it still only around 30-40% cpu load tho. I am still far from convinced just having more cores is better.