So I ported my emulator front-end to the Pi...

[zzip]

And damn does it run sloooowwwww! I don't understand, all the main loop does it read input devices like keyboard, mouse, joystick and update the menu as appropriate, but it takes literally a few seconds to process each keypress! It is written in C and uses SDL2 to create a full-screen kiosk type experience.

 

I guess I'll have to try to figure out where it's wasting its time, but in the meantime, anyone here know about performance with the PI and/or SDL2?

[Flojomojo]

1000 posts!

 

Pi is hella slow. Does your thing try to read the directories, or create a list at boot, or what?

[zzip]

1000 posts!

 

Pi is hella slow. Does your thing try to read the directories, or create a list at boot, or what?

1000? I swear I only posted about 50

 

 

When it launches, it reads theming files, menus, images, etc. But once it gets to the main loop, I tried to minimize the I/O. It will load in boxart & screen-shots if you hover over an menu item for a certain length of time, but it was purposely designed not to load in those images at all if you are quickly scrolling through the menus.

 

I know the pi is slow, but I'm seeing something like 2 seconds from the time I push the down arrow until the screen finally updates! The Pi is not THAT slow!

[RevEng]

Are you running on top of X, or from the console? The latter tends to be a lot faster.

[R.Cade]

The ARM CPUs in the Pi (all of them, although of course newer ones are faster) are really, really slow. (Really). They are designed for power efficiency, not speed. Anything that lets them do modern things (play back video, audio) is done by only with GPU assistance. So, if you are not using the GPU functions to draw your screen, it will be miserably slow.

 

It can be compared maybe to an early 2000's CPUs... so almost 20 years behind in raw speed.

 

https://www.jwhitham.org/2015/04/relative-speed-of-raspberry-pi-pi-2-and.html

 

Think somewhere between 20-30 times slower than even a 2007 Core 2 Duo, or more.

 

From the FAQ ... "Overall real world performance is something like a 300MHz Pentium 2" but I think even that is being generous.

Edited August 3, 2017 by R.Cade

[zzip]

It can be compared maybe to an early 2000's CPUs... so almost 20 years behind in raw speed.

 

https://www.jwhitham.org/2015/04/relative-speed-of-raspberry-pi-pi-2-and.html

 

Think somewhere between 20-30 times slower than even a 2007 Core 2 Duo, or more.

Well I started working on this thing around 2000, so it was designed to work on systems that slow. Of course nowadays it's pushing full HD graphics. But so do a lot of other Pi programs, including other front-ends. So what I'm doing can be done on a Pi, no doubt. I'm just doing something wrong.

 

 

The ARM CPUs in the Pi (all of them, although of course newer ones are faster) are really, really slow. (Really). They are designed for power efficiency, not speed. Anything that lets them do modern things (play back video, audio) is done by only with GPU assistance. So, if you are not using the GPU functions to draw your screen, it will be miserably slow.

This might be what the problem is. I found post describing how to enable an openGL driver that might help, only problem is it says I'm missing a kernel driver when I try, so I'll need to figure that out.

 

Another suggestion I found was to use 16-bit video instead of 32. But when I try that, I get "invalid pixel format" errors. grrr.