Why's Source so "CPU-Expensive"?

[Dario D.]

I've noticed that you could have a scene that's considered mouse-sized on any other engine, but it slows to a CPU-dependant CRAWL on the Source engine, no matter what video card you have.

I would like to know *what it is* that makes source so CPU-hungry.

There are scenes in Unreal Engine 2 with 200,000 polygons and 1024x1024 textures that run 3x as fast as even a tiny scene in Source with only 20,000.

I don't understand what takes the CPU. It's not like the physics objects are simulatng while they're idle.

I'd like to know What CAUSES It in the hopes of making maps that are larger and faster-running on a wider range of CPU's.

Thanks... if anyone knows exactly why.

 

[Penguin929]

physics

 

[Dario D.]

The physics don't simulate when an object is idle...

Because of that, maps run slow with or without them... :O

 

[Pesmerga]

It's hardly dependant on video card specs. Alot of the work is done on the proc, so if that's slow, no gpu in the world is going to make it run nice.

 

[Dario D.]

Any takers?

 

[Argyll]

I would think too it is physics. When there are many ragdoll models on screen or being rendered at one time, even if they are not moving, they still hit performance.

 

[Dario D.]

What concerns me is being in that CS map (Dust or Dust 2) and being in the way far back corner next to a bomb site.

My FPS drops from 50 to like 0.1 FPS if I turn around and look toward the center of the level.

I think it has to do with rendering, regardless of physics I think. My FPS always drops in Dust, regardless, if I fly the camera up into the sky and look down or view too much at once.

I too can only think of physics, but I really think there's something else at work...

Maps like Lockdown NEVER slow down for me. Maps like Overwatch, Dust, Intro_Trainstation (outdoors) slow to a crawl when I view too much.

It's the outdoors for some reason, regardless of the number of physics objects if I'm not mistaken. In my observation, I would think *meshes* are far heavier in Source than other engines.... but that's still a guess.

Something makes Source needlessly heavy for the CPU that other engines don't suffer from. :monkee:

 

[blazertailgunner]

if you make a map and make all the props static, it will run noticably faster then if you make them ragdoll or other physical entity.

 

[$kelet0r]

Could be the size and detail of the skybox
There's usually more than one reason
But it is physics because even when not being interacted with they are not idle in the game world but still fully interactive at all times

 

[bliink]

use the +showbudget function to see whats hogging the most resources and post back here... only problem is that I forgot how to enable it.. someone else post that :E

 

[Pi Mu Rho]

just type +showbudget at the console...

What concerns me is being in that CS map (Dust or Dust 2) and being in the way far back corner next to a bomb site.

My FPS drops from 50 to like 0.1 FPS if I turn around and look toward the center of the level.

your FPS is defined by both your CPU and GPU, not the CPU alone.

 

[bliink]

your FPS is defined by both your CPU and GPU, not the CPU alone.

and if he uses showbudget, then we will see if its a cpu problem (eg, physics is maxing out) or if its just a crappy GPU (world rendering maxing out)

 

[Dario D.]

I'll try it...

Btw, my specs are AMD 2800+ and GeForce 6600 GT. I don't think my specs are a problem in a tiny map like Dust :monkee: