Multi Core Support Suggestion

[Ed Cruse]

All the testing I've done indicate the chip set emulation is actually pretty low overhead, it's the filtering that has high overhead. My suggestion is to move the native mode filtering and displaying to another thread to take advantage of multicore systems. It seems like the messaging would be minimal and as long as the cpu/chipset thread doesn't have to wait much on the filter thread the performance increase on mutlicore systems would be substantial.

So Toni, what do you think? Is this feasable? I have a 2gig 2 core system and I have to run every other frame when scaling to keep the cpu speed and fps up even with full screen. With windowed it's a lot worse. With filtering off it runs way better, almost as good as with RTG.

[prowler]

Hi Ed Cruse,

See the interview with Toni Wilen linked to in this thread:
http://eab.abime.net/showthread.php?t=45681
particularly the discussion about multi-threaded programming.

[Toni Wilen]

Option 1: Use D3D filter, it should be "multicore" as long as display driver and card is good enough.

Most filters are (afaik) mainly memory bandwith limited, not CPU limited so multithreading probably won't help because there still is only one memory bus for both cores. (and display data won't fit in CPU caches)

I previously tried moving RTG copy/color space conversion code (which is similar to filtering code) to separate thread and didn't see any useful improvements, I assume this was also due to memory bandwith limit.

Option 2: buy a new pc

[Ed Cruse]

Originally Posted by Toni Wilen

Option 1: Use D3D filter, it should be "multicore" as long as display driver and card is good enough.

Most filters are (afaik) mainly memory bandwith limited, not CPU limited so multithreading probably won't help because there still is only one memory bus for both cores. (and display data won't fit in CPU caches)

I previously tried moving RTG copy/color space conversion code (which is similar to filtering code) to separate thread and didn't see any useful improvements, I assume this was also due to memory bandwith limit.

Option 2: buy a new pc

The rtg test is disappointing, I was hoping my idea would work, oh well.

I have a question about the D3D filter. I've used it and it's very fast, but the quaility of the display is very poor when scaling. I've found it works very good using windowed with automatic resize, with 1:1 scaling the quality is better then the Scale2x filter. Is the D3D filter supposed to be good quality and there's something wrong with my system or is poor quality normal with D3D when scaling?

My computer isn't old enough yet.