kvm binary names

kvm binary names

[jd]

Hi
   What is the motivation for having different kvm binary names on various linux distributions.. ? 

-- kvm
-- qemu-system-x86_84
-- qemu-kvm

any more ?

Thanks
/Jd


      

Re: kvm binary names

[Daniel P. Berrange]

On Fri, Mar 20, 2009 at 10:57:50AM -0700, jd wrote:
> 
> Hi
>    What is the motivation for having different kvm binary names on various linux distributions.. ? 
> 
> -- kvm
> -- qemu-system-x86_84
> -- qemu-kvm

I can tell you the history from the Fedora POV at least...

We already had 'qemu', 'qemu-system-x86_64', etc from the existing
plain qemu emulator RPMs we distributed.

The KVM makefile creates a binary call qemu-system-x86_64 but this
clashes with the existing QEMU RPM, so we had to rename it somehow
to allow parallel installation of KVM and QEMU RPMs.

KVM already ships with a python script called 'kvm' and we didn't
want to clash with that either, so we eventually settled on calling
it 'qemu-kvm'. Other distros didn't worry about clash with the python
script so called their binary just 'kvm'

Ultimately this mess will resolve itself as all of KVM gets merged into
upstream QEMU and we no longer have a separate code fork. So the regular
QEMU RPM's qemu-system-x86_64 emulator binary will have KVM support
builtin by default

Regards,
Daniel
-- 
|: Red Hat, Engineering, London   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
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Re: kvm binary names

[Bill Davidsen]

Daniel P. Berrange wrote:
> On Fri, Mar 20, 2009 at 10:57:50AM -0700, jd wrote:
>> Hi
>>    What is the motivation for having different kvm binary names on various linux distributions.. ? 
>>
>> -- kvm
>> -- qemu-system-x86_84
>> -- qemu-kvm
> 
> I can tell you the history from the Fedora POV at least...
> 
> We already had 'qemu', 'qemu-system-x86_64', etc from the existing
> plain qemu emulator RPMs we distributed.
> 
> The KVM makefile creates a binary call qemu-system-x86_64 but this
> clashes with the existing QEMU RPM, so we had to rename it somehow
> to allow parallel installation of KVM and QEMU RPMs.
> 
> KVM already ships with a python script called 'kvm' and we didn't
> want to clash with that either, so we eventually settled on calling
> it 'qemu-kvm'. Other distros didn't worry about clash with the python
> script so called their binary just 'kvm'
> 
Don't stop there, why does Fedora have both "qemu-ppc" and "qemu-system-ppc" and 
so forth? There are many of these, "arm" and "m68k" for instance. On x86 I 
assume that they are both emulated, and they are not two names for the same 
executable or such, so what are they and how to choose which to use?

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

Re: kvm binary names

[Glauber Costa]

On Mon, Mar 30, 2009 at 6:12 PM, Bill Davidsen <davidsen@tmr.com> wrote:
> Daniel P. Berrange wrote:
>>
>> On Fri, Mar 20, 2009 at 10:57:50AM -0700, jd wrote:
>>>
>>> Hi
>>>   What is the motivation for having different kvm binary names on various
>>> linux distributions.. ?
>>> -- kvm
>>> -- qemu-system-x86_84
>>> -- qemu-kvm
>>
>> I can tell you the history from the Fedora POV at least...
>>
>> We already had 'qemu', 'qemu-system-x86_64', etc from the existing
>> plain qemu emulator RPMs we distributed.
>>
>> The KVM makefile creates a binary call qemu-system-x86_64 but this
>> clashes with the existing QEMU RPM, so we had to rename it somehow
>> to allow parallel installation of KVM and QEMU RPMs.
>>
>> KVM already ships with a python script called 'kvm' and we didn't
>> want to clash with that either, so we eventually settled on calling
>> it 'qemu-kvm'. Other distros didn't worry about clash with the python
>> script so called their binary just 'kvm'
>>
> Don't stop there, why does Fedora have both "qemu-ppc" and "qemu-system-ppc"
> and so forth? There are many of these, "arm" and "m68k" for instance. On x86
> I assume that they are both emulated, and they are not two names for the
> same executable or such, so what are they and how to choose which to use?
one of them being the userspace linux emulator, and the other, the
system emulator.




-- 
Glauber  Costa.
"Free as in Freedom"
http://glommer.net

"The less confident you are, the more serious you have to act."

Re: kvm binary names

[Daniel P. Berrange]

On Mon, Mar 30, 2009 at 05:12:30PM -0400, Bill Davidsen wrote:
> Daniel P. Berrange wrote:
> >On Fri, Mar 20, 2009 at 10:57:50AM -0700, jd wrote:
> >>Hi
> >>   What is the motivation for having different kvm binary names on 
> >>   various linux distributions.. ? 
> >>-- kvm
> >>-- qemu-system-x86_84
> >>-- qemu-kvm
> >
> >I can tell you the history from the Fedora POV at least...
> >
> >We already had 'qemu', 'qemu-system-x86_64', etc from the existing
> >plain qemu emulator RPMs we distributed.
> >
> >The KVM makefile creates a binary call qemu-system-x86_64 but this
> >clashes with the existing QEMU RPM, so we had to rename it somehow
> >to allow parallel installation of KVM and QEMU RPMs.
> >
> >KVM already ships with a python script called 'kvm' and we didn't
> >want to clash with that either, so we eventually settled on calling
> >it 'qemu-kvm'. Other distros didn't worry about clash with the python
> >script so called their binary just 'kvm'
> >
> Don't stop there, why does Fedora have both "qemu-ppc" and 
> "qemu-system-ppc" and so forth? There are many of these, "arm" and "m68k" 
> for instance. On x86 I assume that they are both emulated, and they are not 
> two names for the same executable or such, so what are they and how to 
> choose which to use?

Those are totally different things.  qemu-$ARCH  is a userspace
emulator, while qemu-system-$ARCH is a full machine emulator. 

The userspace emulator lets you directly execute binaries from the
other non-native arch. The machine emulator provides a complete
virtual machine where you can rnu an entire OS.


Daniel
-- 
|: Red Hat, Engineering, London   -o-   http://people.redhat.com/berrange/ :|
|: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|

Re: kvm binary names

[jd]

Thanks Daniel. 

/Jd

--- On Fri, 3/20/09, Daniel P. Berrange <berrange@redhat.com> wrote:

> From: Daniel P. Berrange <berrange@redhat.com>
> Subject: Re: kvm binary names
> To: "jd" <jdsw2002@yahoo.com>
> Cc: "KVM List" <kvm@vger.kernel.org>
> Date: Friday, March 20, 2009, 11:17 AM
> 
> -----Inline Attachment Follows-----
> 
> On Fri, Mar 20, 2009 at 10:57:50AM
> -0700, jd wrote:
> > 
> > Hi
> >    What is the motivation for having
> different kvm binary names on various linux distributions..
> ? 
> > 
> > -- kvm
> > -- qemu-system-x86_84
> > -- qemu-kvm
> 
> I can tell you the history from the Fedora POV at least...
> 
> We already had 'qemu', 'qemu-system-x86_64', etc from the
> existing
> plain qemu emulator RPMs we distributed.
> 
> The KVM makefile creates a binary call qemu-system-x86_64
> but this
> clashes with the existing QEMU RPM, so we had to rename it
> somehow
> to allow parallel installation of KVM and QEMU RPMs.
> 
> KVM already ships with a python script called 'kvm' and we
> didn't
> want to clash with that either, so we eventually settled on
> calling
> it 'qemu-kvm'. Other distros didn't worry about clash with
> the python
> script so called their binary just 'kvm'
> 
> Ultimately this mess will resolve itself as all of KVM gets
> merged into
> upstream QEMU and we no longer have a separate code fork.
> So the regular
> QEMU RPM's qemu-system-x86_64 emulator binary will have KVM
> support
> builtin by default
> 
> Regards,
> Daniel
> -- 
> |: Red Hat, Engineering,
> London   -o-   http://people.redhat.com/berrange/ :|
> |: http://libvirt.org  -o-  http://virt-manager.org  -o-  http://ovirt.org
> :|
> |: http://autobuild.org   
>    -o-     
>    http://search.cpan.org/~danberr/ :|
> |: GnuPG: 7D3B9505  -o-  F3C9 553F A1DA 4AC2 5648
> 23C1 B3DF F742 7D3B 9505 :|
>