High CPU usage in GZDoom

[Doctrine Gamer]

Hello friends.

When I use GZDoom on my machine processor usage varies from 50% to 70%, I use a processor I5 and a memory with more than 4 gb, so I do not understand how this program can consume as much.

Not logical that he pull 70% of the CPU. In modern games like DOOM 3 BFG Edition CPU usage does not pass or 40% and the ZDoom varies between 25% to 40%.

Even if I turn off all filters and put everything on low, high CPU consumption is the same.

Can someone help me.

(sorry my bad english)

[everamzah]

CL_CAPFPS 1 should cut your CPU usage down. I'm assuming by "put everything on low" you are referring also to the resolution.

[Caligari87]

GZDoom also has all the extra features stacked on top of the old Doom code, which isn't as optimized for modern systems. Barring a complete rewrite of the engine, it's likely to stay that way. Doom3 uses less CPU because it pulls a lot of its needs from the graphics card, while GZDoom is more CPU-dependent and doesn't use the GPU as much.

[GooberMan]

The high CPU usage happens even on stock Doom maps. I suspect ZDoom ups its thread priority and doesn't yield too often, but that's all speculative until I actually look in to the code.

[Doctrine Gamer]

Caligari_87

Is there any program similar to GZDoom not use many CPU resources

everamzah


Thank you! I will use this command to see if it solves anything.

GooberMan

I also do not much idea what it is.

[everamzah]

I should have mentioned, but all cl_capfps does is limits your framerate to 30. Under most circumstances that's probably not what you want.

[Doctrine Gamer]

everamzah

not but anyway thanks for the help

[Blue Shadow]

I should have mentioned, but all cl_capfps does is limits your framerate to 30. Under most circumstances that's probably not what you want.

Alternatively, though it's not the exact same thing, there is [wiki=Display_options#Vertical_sync]vsync[/wiki], which locks the framerate to the monitor's refresh rate.

[Kappes Buur]

Recently there was a bit of a discourse on the subject http://forum.zdoom.org/viewtopic.php?f=12&t=46242
explaining why the CPU is working overtime.

[Doctrine Gamer]

Thanks all for taking my question and I have to use the ZDoom does not weigh on my CPU. I see no other alternative.

like GZDoom but with that high consumption of memory rather I use the ZDoom even he does not have OPENGL. sad but true.

[edward850]

I should have mentioned, but all cl_capfps does is limits your framerate to 30.

35

[Graf Zahl]

The main reason for that high CPU usage is the background OpenGL driver thread. That will occupy one CPU core fully. Not even capping the FPS will help with that. Take that one out and you'll be back to the 40% of other software.

Also, enabling VSync won't help much at all. From what I gathered, the OpenGL driver performs active waiting for syncing, i.e. it doesn't yield the CPU at all.

That means that 50% of CPU resources are already taken, and on top of that come several other background threads, e.g. the sound engine.

[_mental_]

Also, enabling VSync won't help much at all. From what I gathered, the OpenGL driver performs active waiting for syncing, i.e. it doesn't yield the CPU at all.

It depends on particular OS and drivers.
On my pretty old PC with Win7, GeForce 9800, outdated nVidia drivers (can't check exact version at the moment) it did help. On OS X it does help too on any machine I tried. Have no idea about Linux.
So, VSync is a good option to try it out in order to minimize CPU usage.

[Graf Zahl]

Odd. I previously had a Geforce 9600 with Win7 and enabling VSync didn't do much about performance. I haven't checked ever since, though, so maybe something has changed in the drivers.

[Guest]

Hi.
I had same problem even on a Core i7 4.5 Ghz with a 2080 Ti.. one cpu core would be at 90-100% usage all the time!

I also have Beautiful Doom and Hi resolution textures on AND playing at 3440x1440..... There was some lagg rarely BUT!

Then I changed to VULKAN render, and bom! cpu is now 5-10% MAX on EACH core! seriously! and the game runs much better and smooth overall. This is even as it both before and now actually was runing at 60fps.

The OpenGL thing just suck compared to Vulkan!