Dolphin Works better with physical cores than Virtual cores?

[matheusstaffa]

I was testing CEMU recently and saw in their forums that using afinity with physical cores only, would improve emulation speed and it really does.
I'm want to know if that happens on Dolphin too.
Thanks for the help!

[AnyOldName3]

It's not exactly that setting affinity to physical cores makes things go faster (as you can't actually do that, anyway), but instead that because certain pairs of virtual cores share a physical core. If you know that virtual cores 0 and 1 are on the same physical core, and 2 and 3 are on another, and 4 and 5 are on a third core etc. then you can guarantee that you aren't putting two threads on the same physical core if you set their affinity to odd numbers only, for example. For some workloads, this isn't necessary (for example if most of the work done is actually just waiting for memory accesses, a second thread can slip into the empty CPU cycles that would otherwise be wasted, or on a good super-scalar CPU there are enough ALUs to go round) but when both threads want the same resources at the same time, they'll be slower when assigned to the same physical core.

[Helios]

I wouldn't worry about this.

Modern OSes are usually very good about thread scheduling. In my testing on Linux and KVM'd Windows with various thread pinning configs, Dolphin doesn't really see much of a performance boost.