About CPU usage

[VGA]

Hello, I noticed that I could hear my CPU fan while playing Eternity. Then saw that it's using about 50-70% of the two cores of my Core 2 duo e8400 @3.3ghz. For comparison, Zdoom uses half of that.

Is that normal ? Is there some OpenGL option to accelerate ... stuff ?

Also, how do I stop the demos autostarting while I'm in the menus ? It's ultra annoying when the game is raging in the background while I'm looking at the settings.

[Quasar]

VGA said:

Hello, I noticed that I could hear my CPU fan while playing Eternity. Then saw that it's using about 50-70% of the two cores of my Core 2 duo e8400 @3.3ghz. For comparison, Zdoom uses half of that.

Is that normal ? Is there some OpenGL option to accelerate ... stuff ?

Also, how do I stop the demos autostarting while I'm in the menus ? It's ultra annoying when the game is raging in the background while I'm looking at the settings.

For the former, set the video driver to SDL GL2D. If you are still using too much CPU, you'll have to either disable interpolation or even unlatched framerate (these options are also in the video options menu).

For the latter, bring down the console and type endgame. This will drop you to GS_CONSOLE state. There is not currently a means to start the game up already in GS_CONSOLE because, nobody ever requested it, for one.

[VGA]

After enabling GL2D and restarting the game I get full 100% cpu usage. Using fraps I saw that the framerate was correctly at 60 since I had vsync enabled. Disabling uncapped framerate I get normal/low usage.

My vid card is an Nvidia GTX260 with rather new drivers.

EDIT:
Did anyone ever suggest autoexec.cfg ?
:-)

[Quasar]

VGA said:

After enabling GL2D and restarting the game I get full 100% cpu usage. Using fraps I saw that the framerate was correctly at 60 since I had vsync enabled. Disabling uncapped framerate I get normal/low usage.

My vid card is an Nvidia GTX260 with rather new drivers.

EDIT:
Did anyone ever suggest autoexec.cfg ?
:-)

I guess I don't know what ZDoom is doing to simultaneously allow multiple hundreds of FPS and yet use 0% CPU. Maybe one of its programmers will illuminate me on the subject and point out what we are doing wrong. We have sleep calls in all our loops to make sure we give up cycles to other processes but that doesn't seem to be good enough.

I'll look at adding ability to start up into the console state in the next release ;)

[VGA]

In software and without uncapped frame rate it's fine. In software with uncapped it's suboptimal and in gl2d with uncapped it uses up all the CPU. Can you reproduce this?

Also, in your experience, which port is the most compatible with old dehacked-based TCs like Alien and Batman?

Thanks for your attention!

[Quasar]

VGA said:

In software and without uncapped frame rate it's fine. In software with uncapped it's suboptimal and in gl2d with uncapped it uses up all the CPU. Can you reproduce this?

Also, in your experience, which port is the most compatible with old dehacked-based TCs like Alien and Batman?

Thanks for your attention!

The three most compatible maintained ports are Choco Doom, PrBoom+, and then Eternity, in that order. The differences in compatibility are minor between these (for instance PrBoom+ goes very far out of its way to try to emulate stuff like the undefined behavior that happens when maps are constructed completely incorrectly, which I've found to be out-of-scope for EE).

[Csonicgo]

VGA said:

Hello, I noticed that I could hear my CPU fan while playing Eternity. Then saw that it's using about 50-70% of the two cores of my Core 2 duo e8400 @3.3ghz. For comparison, Zdoom uses half of that.

Is that normal ?

It's because ZDoom has a capped frame rate. EE simply pushes as many frames as it can until your CPU cries uncle.

The default cap for ZDoom is 200 FPS, although I've heard from some that in newer development builds, it's as low as 60. For now, you'll need to have Vertical Sync enabled.

[Graf Zahl]

Csonicgo said:

It's because ZDoom has a capped frame rate. EE simply pushes as many frames as it can until your CPU cries uncle.

The default cap for ZDoom is 200 FPS, although I've heard from some that in newer development builds, it's as low as 60. For now, you'll need to have Vertical Sync enabled.

That's one big pile of misinformation.
ZDoom has an OPTION to cap the frame rate, by default it's unlimited.

Of course this cannot be achieved by 0% CPU time, at uncapped frame rate ZDoom uses 100% of one CPU core.

What ZDoom does is go down to 35 fps when the menu is up (i.e the game is paused.)

Using OpenGL usually increases CPU load because a second core will be used by the OpenGL driver. OpenGL also can have the effect that waiting for a vsync is actively waiting, without yielding the CPU core. That also may mean that CPU usage increases.

[Blzut3]

Graf Zahl said:

by default it's unlimited.

CUSTOM_CVAR (Int, vid_maxfps, 200, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)

It has been default limited to 200 since the introduction of vid_maxfps as far as I can tell.

[VGA]

Of course I'm using vsync with zdoom, fraps says 60 and the CPU usage is acceptable.

In eternity engine, for example, even the iwad selection
launcher uses like 60% of the CPU and it's only showing a static picture.

I want uncapped frame rate with working vsync without having to hear my CPU fan working while playing Doom. Also sometimes I do vid encoding in the background, so spare cycles are needed.

Maybe with SDL 2.0 ?

[Graf Zahl]

Blzut3 said:

CUSTOM_CVAR (Int, vid_maxfps, 200, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)

It has been default limited to 200 since the introduction of vid_maxfps as far as I can tell.

Ah, I thought the default was 'unlimited'. I never noticed because in GZDoom it doesn't seem to have any effect. My system happily reports 500+ fps at the start of E1M1, for example, regardless of what this is being set to and the software renderer never goes above 160 when running fullscreen 1920x1080, it never reaches the limit.