On Wed, Dec 21, 2016 at 04:44:08PM +0800, Bob Chen wrote: > -smp 16 > > -smp cores=4,threads=4,sockets=1 > > > Which one has better performance? The scenario is guest VMs running on > cloud server.
It's more complicated than that. The CPU topology (cores, threads, sockets) can be used by guest kernels to make scheduling decisions. If you pin vcpu threads to host cpus and configure the guest with an accurate CPU topology then you can expect the guest kernel to make the best decisions. If you do not pin vcpu threads then you cannot expect any consistent performance advantage by specifying the CPU topology. Stefan
signature.asc
Description: PGP signature
