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Optimizing DosBox for Carmageddon

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First post, by mr_bigmouth_502

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I decided to get back into Carmageddon recently, and since I'm running Linux, I figured the easiest way to do it would be to run the DOS version. It turns out some time ago, the SVN was revised to allow 80-bit FPU precision when compiled for 64-bit. Awesome! Unfortunately, performance with Carmageddon is still kinda crap. 🤣

Running Carmageddon in 320x200 software mode, I get my best performance running with cycles set to max. With a high fixed cycles count, (I've tried 150000 and 200000), performance only gets worse. But here's the weird part; regardless of if I'm using cycles=max or a high fixed cycles count, I NEVER see DosBox even approach 100% CPU usage on any core. I understand DosBox is a single threaded application, but even so, it seems like there's a lot of power it could be using that it isn't using.

Anyway, is there a way I can get Dosbox to use 100% of one of my cores, so that I could (theoretically) get the best possible performance? Would I be better off ditching DosBox entirely and using PCem or a virtual machine instead?

My NEW(ish) desktop:
p8cqsw-2.png

Reply 2 of 7, by Qbix

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(*moved topic to right forum)

Carmagadon is a very very cpu heavy game.
Try setting
cycles = max 105%
to help with the non 100% on one core problem

Water flows down the stream
How to ask questions the smart way!

Reply 5 of 7, by mr_bigmouth_502

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zirkoni wrote:

Having done a little research I've learned that the 64-bit dynarec is supposed to have poorer performance than the 32-bit dynarec. The problem is that it's not easy to install 32-bit DosBox on Arch (well, technically Manjaro in my case). Using a pkgbuild someone shared with me on Reddit, it IS possible to build the SVN in 32 and 64-bit versions simultaneously, but unfortunately compressed audio doesn't work. This is kind of annoying since I'm trying to run the GOG release, which uses OGG files for the CD audio.

Anyway, here's a link to the Reddit discussion containing the pkgbuild in question: https://www.reddit.com/r/linux_gaming/comment … osbox_on_64bit/

My NEW(ish) desktop:
p8cqsw-2.png

Reply 6 of 7, by azn

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First of all Carmageddon crash on 32 bit version, so as for today there is no point trying. Maybe in the future.

Personally I cannot complain as on my about 5/6 years old PC it works just fine but i use two options while running the game:

CARMAV.EXE -NOREPLAY -NOCUTSCENES

Option -NOCUTSCENES rather does not affect gameplay but -NOREPLAY may slightly affect performance as the progress of the race is not being saved so I guess it may speed things up a little bit; but of course I can be totally wrong.

To be honest I would rather like to see working mirror in 3dfx mode than performance boost.