Performance of vdrift (how to increase?)

[reece146]

I've been doing a LOT of testing of car configurations on the 'Ring. It's a blast but it takes along time to get around the track so comparing lap times is a slow process.

I started using LeMans (yawn) because it is roughly half the time around the track (~5min vs ~10 min).

But, I'm seeing the frame rate noticably drop and the screen is even choppy at times.

How I'm running:

- Mac OS X 10.4.8
- Dual G5 @ 2.0 GHz
- 1.5 GB RAM
- 1600x1000 res at 32bpp
- windowed, full texture and viewing distance.

If I go full screen it helps a little bit. I could dump the resolution down but if I did that then it wouldn't be "like being there".

What can I do to increase frame rates in the visually interesting parts of the track? Buying a new Mac is easily a few years away still.

- new display card? I have a 128 MB ATI Radeon 9800 Pro currently. The newer Mac friendly ATI NVIDIA stuff must be much faster? Is the frame rate fully GL bound? There's the X800 XT and FX5200 in a semi reasonable price range for Macs. X1800 and FX7300 is shipping in the new ones but not AGP.

- More RAM? vdrift appears to take 184MB of real ram, 460MB of virtual ram... which seems to be a lot.

- Mac specific compile options? I wanna start compiling SVN anyway.

- something else?

Any insights appreciated.

[cotharyus]

I'm running very much the same game settings as you, but running full screen and haven't seen a frame rate below 50 fps. For what it's worth, I think it's your video card, not the rest of your system.

[reece146]

I'm running very much the same game settings as you, but running full screen and haven't seen a frame rate below 50 fps. For what it's worth, I think it's your video card, not the rest of your system.

Which display card are you using?

Looks to be several options - from $100 to $800 <yikes>.

Maybe it is just the amount of video RAM that is the issue?

When I go on the 'Ring I do see the terrain being rendered off in the distance but it doesn't seem to affect frame rate (much).

[cotharyus]

Nvidia 6800GT (256M DDR3) PCIe

[joevenzon]

Running at such a high resolution, your video card is likely the performance bottleneck. Upgrading to an NVIDIA 6800+ or 7800+ is recommended... I don't know anything about ATI cards, unfortunately.

[thelusiv]

The other option is to turn down VDrift's Display settings a little. Changing from full view distance to medium will probably make a big difference, especially in those spots where you see a big drop usually. Try that until you get that new video card...

[reece146]

I've been doing a little more research and it seems that upgrading to a ATI X800 XT is probably the best bang for the buck. Unfortunately, my G5 is AGP (c. fall 2003) so I don't have any PCI-e options <$#@! />.

I got a peice of software to overclock the GPU. Just about to reboot (loads kernel extension) to see if it does anything.

Edit: Overclocking the GPU ~15% and the display memory ~8% helps playability but is the edge of where artifacts appear on the screen. It'll do until I can get some new hardware on the go.

[reece146]

I figured I'd update this thread with latest results of a upgraded display card.

The original ATI 9800 was starting to die - lots of screen blit type artifacts and it was getting progressively worse.

Unfortunately, because of the vintage of my computer upgrading it was not very straightforward. It is AGP and the options are limited with it being a Mac and all. At the end of the convoluted oddyssey (don't ask) I ended up with an NVIDIA 7800GS with 256MB DDR3 (Mac EEPROM flashed PC Card).

Now I am able to run at 1680x1050 with everything turned on and it rocks! There are a few places where it bogs briefly (Mosport at the Canada government sign for example) but otherwise I'm really happy.

But, race mode still sucks. Frame rates of ~5 FPS when racing against the XS at Mosport. If I switch res to 1024x640 then my FPS goes up to ~8-9 FPS but it still sucks as there is lag between the keyboard input and what happens on the screen (FPS counter not accurate?).

If I turn off all the eye candy like reflection, anti-aliasing, low texture size, etc., etc. the game is a touch more playable but the FPS counter still hovers at around 5 FPS or so.

Anyway, that is what I've found. I thought I remembered someone mention that the collision code might not be as quick as it could be. That might explain why playing aginst another car put the frame rate in the toilet? FWIW, the other car game that we play ( Redline :: http://www.ambrosiasw.com/games/redline/ ) is smooth as silk on this new display card; it was on the old card too for that matter.

Oh well, I'm just happy to be able to have a functioning PC at home so that I can get back at making the .car file for the Impreza.

[thelusiv]

Congrats on the new video card...

On the Impreza, I'm glad you're going to take a look at it. I think there is a problem with the AWD cars going too fast and maybe you can help figure it out...

[reece146]

Congrats on the new video card...

On the Impreza, I'm glad you're going to take a look at it. I think there is a problem with the AWD cars going too fast and maybe you can help figure it out...

Yeah, I'm going to start with the suspension geometry and go from there. My "gut" says there is a algorithmic issue with the AWD wrt how power is spread to the wheels. That means I'll finally need to dig into the source code.

[thelusiv]

Let me know if you need any help digging through code, I know my way around pretty well at this point...