[mythtv] Porting to Play Station 2

[Neil Trodden]

At 11:44 31/12/2002 -0500, you wrote:
>Having not read your link yet (next to do :-)) I still wonder how much
>RAM is available after you are sitting in X at a shell on your PS2.
>
>How can you say the RAM is not an issue if there is 8MB left of main
>memory and the current Myth apps + decoder + buffers take 12MB?  I have
>no idea what the actual numbers are though. So how much is left on your
>Ps2 setup?  and maybe Isaac can tell us how much he thinks the player
>needs.  (I assume you are right and "some" things can be swapped to
>disk, but you wouldn't want much to swap; I would think you would just
>kill off unneeded things to keep swapping down).
>
>Thanks for the reply!  What do you think about the Linux PS2 overall?
>is it worth playing with?
>
>Mike

Sorry for the late reply,

I haven't used the kit for a while so I will get round to getting some hard 
memory
figures soon!

Under X, things are a bit slow. The general consensus is that running under 
x is
a pain. gcc is slow as are all applications. i386 cpus are, by design, good
all-rounders for running many different types of applications. The emotion 
engine
is geared towards processing large volumes of geometric data and rendering it.
For this it is very, very fast.  A recent demo, optimised for the ps2, renders
570,000 vertices per frame at 60fps. Stuff just has to be written 
specifically to
use the vector processors, the graphics synthesiser and the emotion engine.

The odd thing is that you talk directly to the graphics hardware so
ps2 graphics programs run directly from the console (no x at all...). If 
you wanted
a full implementation of mythtv then it would be very slow if you used x and qt
on the ps2. If you created a stand-alone player for pre-recorded shows, 
using the
ps2 as the "front end" then that might be more realistic. You'd have to ditch x
to get any real performance so you'd need to re-implement the gui.

I wonder how hard it would be isolate the decoder part into a c command 
line app,
just to benchmark its speed at decoding? We could forget about the display 
for now.
Something like:

benchmark testfile.nuv

avg fps : xx.x

If anyone could give me a "point" in the right direction, I'll have a look 
but I don't know
a lot of c yet.


Neil Trodden