On Wed, Jun 19, 2019 at 11:22:23AM +0800, Meiyo Peng wrote:
> Hi Florian,
> 
> Florian Pelz writes:
> 
> >  @example
> > -qemu-system-x86_64 -m 1024 -smp 1 \
> > +qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
> ...
> > -The ordering of the drives matters.
> > +The ordering of the drives matters.  @code{-enable-kvm} is optional, but
> > +significantly improves performance, @pxref{Running Guix in a VM}.
> 
> "-enable-kvm" is deprecated.  Please use "-accel kvm" instead.  QEMU
> will probably support "-enable-kvm" option forever but "-accel kvm" is
> recommended.
> 
> 
> 

Thank you Meiyo Peng!  I cannot find an official deprecation, but
-accel seems to be recommended in general.  But I am unsure.  I like
-accel; it seems less KVM-specific, that is better.

However, I cannot find -accel kvm in Debian Jessie’s manpage at

https://manpages.debian.org/jessie/qemu-system-x86/qemu-system-x86_64.1.en.html

and in a Debian Stretch VM it says: qemu-syems-x86_64: -accel: invalid
option

Maybe it is better to wait three more years until switching to -accel
so instructions work on Debian (LTS)?  If Guix wants to switch now
though, see the attached patches.

Regards,
Florian