I can see no reason why it should be slow down any emulation, or any other program.

The first question you have to ask yourself is this:

In which situation would the the process/thread switch to a different core?

MiniMax wrote:

I can see no reason why it should be slow down any emulation, or any other program.

The first question you have to ask yourself is this:

In which situation would the the process/thread switch to a different core?

You know the snes and how it has special chips in some games? Now, is it faster to emulate the base snes in one thread and the special chip in a second thread?

I dunno, but if you have 2 threads (base + special), and a CPU with 2 cores, then there is no need to switch the thread to a different core is there?

Well, I am after a way to make it so that single threaded programs run on a single thread. I do not wish to use the affinity setting.

people with core 2 duo's say bsnes runs on a single thread for them but for me it does not.

Single-threaded programs by definition always run on a single-thread.

Yet they do not on my machine. DOSBox does not use one thread on my machine.

Then DOSBox is not single-threaded.

Are you sure? and here are some screenshots of taskmanager...

http://i63.photobucket.com/albums/h133/franpa … untitled-10.png [doing nothing]
http://i63.photobucket.com/albums/h133/franpa … untitled1-1.png [running bnsf (a NSF music player)]

trust me there is something that is slow, i believe if a program is split into 2 threads and the 2 threads need too communicate with each other to stay in sync, you would take a performance hit everytime that occurred right?

sorry, i can't think of the term im after in regards to what im talking about... is it Context Switching?

Looks like DOSBox has 8 threads

Ok, I have done some checking and will get back to you tomorrow or something about this... I could be wrong 😜

http://board.zsnes.com/phpBB2/viewtopic.php?t … 4510&start=5700
So, does DOSBox use more then one kernel-level thread?

Dunno what a kernel-level thread is supposed to be but DOSBox has one thread that does most of the work and some others that mix the sound, read input devices and such.

I'm aware it is wikipedia but still... http://en.wikipedia.org/wiki/Thread_(computer_science)

And your question was?

It explains what a kernel-level thread is?

Yes.

I guess Windows threads are kernel-level threads then...

Dosbox does get scheduled from one core to another. That is how windows scheduler works, it checks which core is used less so it schedules the next slice to that core. Does that make single thread programs slower? Dunno, maybe. Can I do anything about it? Write a better scheduler or set process affinity. Can I make windows see only 1 core? Check your bios or change Computer to ACPI Uniprocessor PC. But I wouldn't recommend that, it is better to set the affinity.

MiniMax wrote:

In which situation would the the process/thread switch to a different core?

So potentially at the beginning of each time-slice, after the CPU has already destroyed registers, polluted the cache etc, in order to run the scheduler code?