Setting CPU affinity

[hellbringer616]

Just wondering, since PCSX2 only uses 2 cores on my new quad. If i set the affinity to cores 0/1 will i see speed up/slow down? Or no?

[echosierra]

Just wondering, since PCSX2 only uses 2 cores on my new quad. If i set the affinity to cores 0/1 will i see speed up/slow down? Or no?

I don't think anything will happen. The OS is usually much much better at managing thread/process affinity than us mere mortals, if anything I'd expect it to slow down slightly because you're overriding it.

Even though PCSX2 only uses 2 cores, you may see usage on all 4 due to how the OS balances the load. It's in the best interest of the hardware to keep it even, and the OS will auto-magically move threads around as needed.

[Shadow Lady]

Try it and see for yourself, it may change the behavior on different machines.

[iakoboss7]

Just wondering, since PCSX2 only uses 2 cores on my new quad. If i set the affinity to cores 0/1 will i see speed up/slow down? Or no?

Even though PCSX2 only uses 2 cores, you may see usage on all 4 due to how the OS balances the load. It's in the best interest of the hardware to keep it even, and the OS will auto-magically move threads around as needed.

thats true there was times i could see pcsx2 using all 4 cores almost the same in kingdom hearts, ofc not all the time but it was something xD
for devs: cant u try something like pcsx2 forces os to split the usage? it happens rarely but if it could happen all the time it would be realy good.
its just a thought maybe its stupid.

[echosierra]

Just wondering, since PCSX2 only uses 2 cores on my new quad. If i set the affinity to cores 0/1 will i see speed up/slow down? Or no?

Even though PCSX2 only uses 2 cores, you may see usage on all 4 due to how the OS balances the load. It's in the best interest of the hardware to keep it even, and the OS will auto-magically move threads around as needed.

thats true there was times i could see pcsx2 using all 4 cores almost the same in kingdom hearts, ofc not all the time but it was something xD
for devs: cant u try something like pcsx2 forces os to split the usage? it happens rarely but if it could happen all the time it would be realy good.
its just a thought maybe its stupid.

They can't really do much about it. It isn't a 'true' quad-core usage, moreover it's an artifact of the OS trying to visualize the core loads in a way that would make sense to a person. PCSX2 isn't really using all 4 cores at once, but the programs it makes calls to (DirectX or something) may very well execute on another core.

Trust in the devs if it hasn't been implemented I'm sure there's a very good reason.

[iakoboss7]

They can't really do much about it. It isn't a 'true' quad-core usage, moreover it's an artifact of the OS trying to visualize the core loads in a way that would make sense to a person. PCSX2 isn't really using all 4 cores at once, but the programs it makes calls to (DirectX or something) may very well execute on another core.

Trust in the devs if it hasn't been implemented I'm sure there's a very good reason.

i dont speak about really using them all 4 its just as u say. our devs ftw but i thought of suggesting that xD

[Air]

Generally speaking, it's always best to rely on the kernel as much as possible for the low-level thread scheduling. The kernel "knows" a whole lot more about the state of the system than PCSX2 ever could, and it also has access to special cpu tasking and sleep/wakeup tools that user-mode programs can't touch.

Additionally, in Windows at least, different cpu/chipset drivers are provided that typically handle the user's CPU more efficiently than end-user software could (some CPUs work better with load balancing than others, for example). Finally, there's the added complexity of hyperthreading, which must use a rather different scheduling algorithm to be taken full advantage of. So yea, it's just complicated, period.