Janne Johansson <icepic...@gmail.com> wrote: > Den ons 1 feb. 2023 kl 03:08 skrev Justin Muir <ve7...@gmail.com>: > > I've got an AMD A10 with 4 cores and only 2 are online. I'm not sure how to > > enable the other 2. > > > > hw.ncpufound=4 btw > > Any ideas out there? > > OpenBSD disables hyperthreading (or symmetric multithreading, smt), so > if your "4-core" cpu is actually 2 real cores and 2 hyperthreads, then > this sounds perfectly reasonable. > > For example, this box of mine (not the same cpu, but still), it looks like > this: > > hw.ncpufound=8 > hw.smt=0 > hw.ncpuonline=4 > > so I get the 4 real cores running out of possibly 8.
You can read up on the micro-architectural risks of the specific cpu you have, and your usage pattern, and make your own decision. I have machines where I enable it, but a safe default is the right choice for us to make.
