SDL_VIDEODRIVER=dga allocates too much memory

SDL Development
1

Hi!

I’m talking here about SDL-1.1.6, redhat-6.2 and kernels 2.2.18 and 2.4.1.
When using VIDEODRIVER=dga, it allocates quite a lot of memory compared do
X11 (i.e. SDL_VIDEODRIVER not set). More precisely: calling

SDL_Init(SDL_INIT_VIDEO | SDL_INIT_EVENTTHREAD | SDL_INIT_NOPARACHUTE)

allocates (on one sample) about 8MB when using X11, but about 33MB when
using DGA. On a second sample on a second computer (same software but
different hardware), I don’t know the amount caused directly by SDL_Init,
but top says the program has 15M with X11 and 33M with DGA. So apparently
this isn’t a problem with something on my side. Can someone explain this
please (and eventually fix it)? Please CC me, I’m not on on the list.

Bye,–
It is easier to fix Unix than to live with NT.

2

I’m talking here about SDL-1.1.6, redhat-6.2 and kernels 2.2.18 and 2.4.1.
When using VIDEODRIVER=dga, it allocates quite a lot of memory compared do
X11 (i.e. SDL_VIDEODRIVER not set)

This is caused by the memory map of the video card. I’m guessing that you
have a 16 MB video card. The program isn’t using system memory, but the
memory map still shows up in the output of top. The X server shows the
same behavior.

See ya!
-Sam Lantinga, Lead Programmer, Loki Entertainment Software

3

Sam Lantinga wrote:

I’m talking here about SDL-1.1.6, redhat-6.2 and kernels 2.2.18 and
2.4.1. When using VIDEODRIVER=dga, it allocates quite a lot of memory
compared do X11 (i.e. SDL_VIDEODRIVER not set)
This is caused by the memory map of the video card. I’m guessing that you
have a 16 MB video card. The program isn’t using system memory, but the
memory map still shows up in the output of top. The X server shows the
same behavior.
Aha, so you say it doesn’t/shouldn’t have impact on the performance?. hmm
could be. However, the 33-8=25MB difference is on a 16M card and 33-15=17M
is on a 8M card, which is strange IMHO (if it was > 2*vmem on both I’d
guess double buffering, but it’s the same program). Any ideas? I guess I’ll
be buying more memory tomorrow anyway and forget about ±30MB :wink:

Thanks for speedy reply.–
The three Rs of Microsoft support: Retry, Reboot, Reinstall.