Re: [gentoo-user] Re: [OT] Any centralized documentation on qemu-kvm?

[Bill Kenworthy]

On Wed, 2010-07-14 at 21:15 -0700, walt wrote:
> On 07/13/2010 08:54 PM, Walter Dnes wrote:
> >    Before anybody asks...
> > 1) VirtualBox manages to do a hard locup on my Intel I3
> > 2) qemu depends on softmmu, which requires gcc 3.x
> >
> >    So I installed qemu-kvm (different from qemu).  The documentation that
> > I've found via Google is out-of-date/irrelavant.  I know that there is a
> > "kvm" command, and typing "qemu{TAB}{TAB}" gives me...
> >
> > waltdnes@i3 ~ $ qemu
> > qemu                qemu-io             qemu-system-x86_64
> > qemu-i386           qemu-kvm            qemu-x86_64
> > qemu-img            qemu-nbd
> >
> >    Of the 9 commands, only qemu, qemu-img, and qemu-nbd have man pages.
> > So RTFM becomes a little harder<G>.  Are there any up-to-date central
> > locations for qemu-kvm documentation?
>
> Well, wait a sec.  I track both qemu and qemu-kvm from their git repositories
> rather than the gentoo packages, so YMMV.
>
> One potentially very confusing thing between the two products is that the
> primary command-line program for qemu is (what else?) "qemu", but for qemu-kvm
> the primary command-line program is qemu-system-x86_64. (Only 64-bit machines
> with hardware virtualization support will run qemu-kmv, AFAIK.)
>
> BUT BEWARE:  both qemu and qemu-kvm supply a file named qemu-system-x86_64, and
> they are not at all the same file, so you cannot have both packages installed in
> the same --prefix.  (I don't know how gentoo resolves that conflict.)
>
> I install the git version of qemu in /usr/local, and qemu-kvm in /home/wa1ter,
> so I have to be careful to type the --prefix when I run one or the other.
>
> qemu-kvm does not supply a command named 'qemu', so there is no name conflict
> in that particular case.  If you type 'qemu-system-x86_64', however, you will
> get completely different results depending on which package you are actually
> executing, so watch it!
>
> AFAICT, the command-line flags for 'qemu' and 'qemu-system-x86_64' are identical
> at least for simple stuff, though I never use the super-anal-compulsive flags
> for complicated networking/bridging/firewalling stuff, so I can't comment on it.
>
> My impression from experience is that qemu-img is the same for both packages,
> but I'm careful anyway to use the matching version, just in case.
>
> For the short term, I'd say you can use the regular qemu docs for looking up what
> command-line flags to use with qemu-kvm.  If you find any exceptions, please let
> us know.
>
>

Coming in late, if qemu is different to qemu-kvm, what is different
about running "qemu --enable-kvm" - "man qemu", v0.11.1.

As you say, documentation on this stuff is a bit lacking.

BillK