Silly Question

[Little Bear]

What makes one computing task harder than another? For example why are graphics harder for the computer to run, than using a calculator in one static string (1*6+8=14 not 1*6=6+8=14) (if I don't make any sense I am sorry ).

[burnttoastnice]

There was a techquickie posted on this some time back. Long story short, GPU workloads are heavily parallelised, which is why graphics cards have several more 'compute cores' compared to a desktop CPU.

[minibois]

Wait, what are you asking?

You're comparing two completely different things here. It's like me asking "why is it for a human harder to run a marathon than doing a sprint?"  it's two completely different things which ask for completely different ways of working.

 

Graphics are done by the GPU (whether integrated or dedicated) and stuff like those calculations are done by the CPU. Graphics rendering is much more intense than a simple command. Graphics rendering is depended on meshes, textures, UV mapping, etc. etc.

[LizardsAreOP]

3 minutes ago, Minibois said:

completely different ways of working.

how is it different way of working? GPU's render the same way they render Pacman or GTA 5 just GTA 5 would be much more tense

[ShadowCaptain]

7 minutes ago, Little Bear said:

What makes one computing task harder than another? For example why are graphics harder for the computer to run, than using a calculator in one static string (1*6+8=14 not 1*6=6+8=14) (if I don't make any sense I am sorry ).

Seems pretty obvious no?

 

Calculating a sum, is a couple of steps, the computer just does simple maths using barely any processing power

 

playing a video game, the computer has to calculate the physics of every object, character and item on screen, render and display the graphics, work out where the player is compared to the enemy players, work out where each bullets lands, render the graphics of every object, display the game 60 times per second, connect to an online lobby to update the location of each player constnatly, as well as every bullet the enemy fires

I mean.. obviously doing that takes more processing power than the computer doing 12+6 - think of how many thousands of parallel tasks the GPU and CPU have to do

[minibois]

8 minutes ago, LizardsAreOP said:

how is it different way of working? GPU's render the same way they render Pacman or GTA 5 just GTA 5 would be much more tense

Well that is a 2D and a 3D game, Pacman doesn't have to render light (for example raycasting) and it doesn't have to think about render distance, etc. etc.

But what I understood from OP is he asked why it is harder to render graphics, than just doing a simple calculation

[Nuluvius]

Just now, ShadowCaptain said:

Seems pretty obvious no?

Indeed, one could simplify the explanation by saying: It's the same thing but many many more layers of it and at a much greater volume.

[Little Bear]

5 minutes ago, Minibois said:

Wait, what are you asking?

You're comparing two completely different things here. It's like me asking "why is it for a human harder to run a marathon than doing a sprint?"  it's two completely different things which ask for completely different ways of working.

 

Graphics are done by the GPU (whether integrated or dedicated) and stuff like those calculations are done by the CPU. Graphics rendering is much more intense than a simple command. Graphics rendering is depended on meshes, textures, UV mapping, etc. etc.

You actually, somewhat got my question. Of course they are different, but I am asking why is it more "intense", and do you really think I am as stupid to think it is as simple as one command? I said for example. For the record, whether it is integrated or dedicated, CPU or GPU, it all boils down to base line the same thing (in low level computation).

[LizardsAreOP]

1 minute ago, Minibois said:

Well that is a 2D and a 3D game, Pacman doesn't have to render light (for example raycasting) and it doesn't have to think about render distance, etc. etc.

But what I understood from OP is he asked why it is harder to render graphics, than just doing a simple calculation

Ok lets compare GTA 4 and GTA 5,the GPU works the same but GTA 5 is more tense to render due to obvious reasons

[HeadsUpHigh]

Graphics are by their nature more complex and thus require specialised hardware to be used so they can be executed efficiently, which is why we have gpus.

 

If you are asking why graphics are hard for the CPU to render, that's because the CPU is a generic processing unit which in turn comes with the downside of not being very efficient on specialised tasks.

 

If you are asking why graphics software is harder to design and more complex, that's because a) graphics are by default more complex, and b) because the specialisation of the gpu comes with the cost of reduced generic capabilities and thus requires the programmer to completely adapt to the high-parallel programming paradigm that they use. 

 

Just to give you an example, if you are using a switch/if statement on a cpu -bound code block, worst case scenario you end up flushing the cache and lose a few circles. If you use a switch/if statement on let's say shaders, the result of calculating the statement might be to have half of the shaders on a compute unit to run 1 type of shader and the other half another. What will happen is that all of them will run the same shader and then switch to the other one, resulting in half of your hardware processing power being wasted.

[Little Bear]

5 minutes ago, ShadowCaptain said:

Seems pretty obvious no?

 

Calculating a sum, is a couple of steps, the computer just does simple maths using barely any processing power

 

playing a video game, the computer has to calculate the physics of every object, character and item on screen, render and display the graphics, work out where the player is compared to the enemy players, work out where each bullets lands, render the graphics of every object, display the game 60 times per second, connect to an online lobby to update the location of each player constnatly, as well as every bullet the enemy fires

I mean.. obviously doing that takes more processing power than the computer doing 12+6 - think of how many thousands of parallel tasks the GPU and CPU have to do

Again It was an example.

[LizardsAreOP]

3 minutes ago, Little Bear said:

You actually, somewhat got my question. Of course they are different, but I am asking why is it more "intense", and do you really think I am as stupid to think it is as simple as one command? I said for example. For the record, whether it is integrated or dedicated, CPU or GPU, it all boils down to base line the same thing (in low level computation).

a GPU can more calculations and render more faster than a iGPU its just that the graphics,light,resolution,textures make it complex

[Little Bear]

4 minutes ago, LizardsAreOP said:

a GPU can more calculations and render more faster than a iGPU its just that the graphics,light,resolution,textures make it complex

I wasn't talking about hardware, more so software in that case. I might seem technologically illiterate, but I am not. Thank you though for trying <3

[ShadowCaptain]

5 minutes ago, Little Bear said:

You actually, somewhat got my question. Of course they are different, but I am asking why is it more "intense", and do you really think I am as stupid to think it is as simple as one command? I said for example. For the record, whether it is integrated or dedicated, CPU or GPU, it all boils down to base line the same thing (in low level computation).

 

Yes its all simple commands at the bass level 

 

but some programs could be doing thousands of them every single second, which obviously requires more power

 

Not really sure what else there is to say?

[minibois]

7 minutes ago, Little Bear said:

You actually, somewhat got my question. Of course they are different, but I am asking why is it more "intense", and do you really think I am as stupid to think it is as simple as one command? I said for example. For the record, whether it is integrated or dedicated, CPU or GPU, it all boils down to base line the same thing (in low level computation).

Nah, of course I don't think you're stupid. It's a very valid question, which I answered in a kind of dick way.. Sorry.

What I meant to just say that the two are very different. For example graphics have to calculate the different vertexes (polygons) of the object and depending on the way the engine works with models it might have to splice up the texture to fit it on the object. That just makes it so graphics are many many calculations, while a simple small calculation is just one.

This is also why GPU's generally have some faster stuff, like GDDR5. It has to pass along all this data many times per second, thus it needs to be VERY fast. 

7 minutes ago, LizardsAreOP said:

Ok lets compare GTA 4 and GTA 5,the GPU works the same but GTA 5 is more tense to render due to obvious reasons

Well, yeah, but OP was not asking why one game is harder to render than another, he was asking why graphics rendering is more intensive than a simple calculation. (also, GTA IV might even be harder to render than GTA V, because it's optimized like shit ) 

[LizardsAreOP]

2 minutes ago, Little Bear said:

I wasn't talking about hardware, more so software in that case. I might seem technologically illiterate, but I am not.

Lets say you have notepad opened now copy a really really really long text so big you cant even read it so big the file is 10gb and imagine how much would it take to put all those letters in the sheet forever,the operating system has to do all that and the CPU and to calculate and its a very stressful procces even tho its just a paper sheet its allot about size and compexity

[Little Bear]

So what I gather, Its what you would assume, more calculations = more processing power necessary. That is what i previously thought, but wondered if it was more complicated than that.

[LizardsAreOP]

1 minute ago, Little Bear said:

So what I gather, Its what you would assume, more calculations = more processing power necessary.

Yes like i said does not matter whatever it is even some letters if its huge it can be very complex

[Little Bear]

7 minutes ago, Minibois said:

(also, GTA IV might even be harder to render than GTA V, because it's optimized like shit ) 

100% true.

[HeadsUpHigh]

8 minutes ago, Little Bear said:

So what I gather, Its what you would assume, more calculations = more processing power necessary. That is what i previously thought, but wondered if it was more complicated than that.

Almost. The CPU can actually render. The problem is almost never about software, it's about hardware. Hardware limitations are usually what defines the programming paradigms you are going to use on each situation. Since the CPU is a generic processing unit, it does have the ability to render at very slow speeds. Trying to increase the power, you eventually hit walls of physics and that's when you start needing specialised hardware to do the specific task. Old computers used to do rendering on the cpu, and since parallelism did not exist back then ( because we didn't need it) the cpu was rendering line by line of pixels. When we got to the point where cpus wouldn't cut it for graphics we designed new chips that would be capable of rendering not 1 pixel after another, but multiple pixels at the same time. The amount of pixels that can be rendered at the same time has increased with time, as well as the amount of calculations done before each pixel is being rendered.

 

This is a long story that basically boils down to the fact that cpu and gpu calculations can't be compared because they are inherently different because they use different math. A task requiring more calculations on a gpu could be potentially made to need less on a cpu and be executed more efficiently there.

 

In the same way that a cpu can render an image, you can also use a gpu to do generic processing, called GPGPU( generic processing graphics processing unit). The difference between rendering on a cpu and gpgpu is the fact that gpgpu can potentially be beneficial for tasks that can be parallelised more than a cpu can support. So you can potentially take a task that is being done on a more linear way on a cpu and rewrite it to take advantage of the gpu's parallel architecture. This is done for example on deep learning and on other projects like Folding@Home and more.

[Little Bear]

2 minutes ago, HeadsUpHigh said:

Almost. The CPU can actually render.

 

you can also use a gpu to do generic processing

Thanks for the Information, you nailed exactly what I was looking for, but don't you think these two things are kinda obvious? If you have an iGPU then your using your CPU to render, and if you bitcoin mine more than likely your using your gpu to do it.

[HeadsUpHigh]

2 minutes ago, Little Bear said:

Thanks for the Information, you nailed exactly what I was looking for, but don't you think these two things are kinda obvious? If you have an iGPU then your using your CPU to render, and if you bitcoin mine more than likely your using your gpu to do it.

The OS will always prefer to use any gpu available to render, even intel hd2000 are better than an i7 6700k on rendering. I have no idea how bitcoin mining works so I don't know what is the optimal hardware for it.

 

What do you mean about the obvious part ?

[Little Bear]

3 minutes ago, HeadsUpHigh said:

What do you mean about the obvious part ?

CPU's being able to GPU's jobs and vice verse. Forget about it though you answered my question whether you realize it or not.

[HeadsUpHigh]

1 minute ago, Little Bear said:

CPU's being able to GPU's jobs and vice verse. Forget about it though you answered my question whether you realize it or not.

Alright cool

[straight_stewie]

10 hours ago, Little Bear said:

What makes one computing task harder than another? For example why are graphics harder for the computer to run, than using a calculator in one static string (1*6+8=14 not 1*6=6+8=14) (if I don't make any sense I am sorry ).

This particular question is asking what the difference between a sequential task and a parallel task is. Another part of this question is mathematical or logical difficulty. Some things require more advanced mathematics or logic than others. Another part of this question could be Np-Completeness.

Some things are harder than others because they are highly parallel. Some things are harder than others because they require more complex math (for example, calculus is harder than algebra). Some things are "harder" because computers aren't good at solving that particular type of problem, or no good way has been found to solve that problem.