dosbox already does multithreading with graphics updates being done in another thread, but that's about the only thing you can do with it.

From what I`ve been reading about Multi-threading, its not that great anyway. Works in the exact same way that windows does multi-tasking.

Alot of the older games don't support it either.

You are mixing two things. Of course more processors help with more threads.
Another thing is the current Intel's technology when one processor present itself as two virtual processors. This just saves windows overhead in switching threads.

Mirek

Harekiet wrote:

dosbox already does multithreading with graphics updates being done in another thread, but that's about the only thing you can do with it.

Interesting. Any idea of how much of a performance boost it gives? Say, comparing one 2ghz to two 2ghz, or something like that. To raise the cycles by 10% in a demanding game?

I'm fully aware of it's a bit stupid thing to ask since it varies from game to game but, erm, I'm interested in some kind of answer anyway 😜

Freddo wrote:

Interesting. Any idea of how much of a performance boost it gives?

On a dual PIII 933 system, running Wing Commander II under 0.63 with cycles=5000, top reports about 70% CPU usage from one dosbox thread and 0.4% from the other (this is in combat). Of course, top is notoriously unreliable under 2.4, but that should give you some idea.

The real benefit of dually is that the processor which isn't sweating under DOSBox can keep other stuff running 😀

Thanks 😀

The multithreading isn't used anymore for better timing 😀

Ah, ok 😀

More precisely: there were problems with sound quality when using multi-threading.

Mirek

Just a bit of FYI: I compiled 0.63 with the Runtime Libraries option set to Single-Thread in Visual C++ .NET 2003. When I ran DosBox, I got the Command Prompt window to display, but that was it. Since the DOS window remained open, I make a quick inspection of the process using Task Manager to see that it was still running but not using any CPU time.

I recompiled with the Runtime Libraries set to Multi-Threading, and DosBox ran as expected. I have not intimately investigated the code, but I suspect Multi-Threading is still used ...somewhere!

dosbox itself doesn't use multithreading anymore.
maybe sdl does (it does on linux for audio)