Re: [Qemu-discuss] Getting qemu-system-i386 to use more than one core on Cortex A7 host

[Peter Maydell]

On 3 January 2016 at 20:57, David Durham <address@hidden> wrote:
> Any suggestions or comments on how to do this are very welcome
> ... I built qemu with --target-list i386-softmmu and when I run
> qemu, top only shows one qemu-system-i386 using 100% of one core

This is expected. Our current emulation is single threaded
even when emulating multiple target CPUs, so we'll only
use one host core. (We do have some helper threads for a
few IO tasks etc but those are not cpu-bound.)

There is some development work in progress to try to
make better use of multi-core hosts but it's not very
far advanced yet. (Also emulating x86 guests on arm hosts
with multiple cpus might not ever be supported because
the x86 memory model would require barriers everywhere
and it's not clear it would overall improve performance.
ARM-on-x86 is the primary initial usecase.)

thanks
-- PMM