Utility to see if kvm acceleration can be used

And the script.

kvm doesn't current depend on python, and doesn't require it, so adding this script would add a dependency which could be avoided by using a shell script and grep (both of which are guaranteed to be installed). Furthermore, kvm falls back to qemu from the internal code: perhaps abstracting this for an extra utility would be simple enough?

Oh, I thought kvm did require Python already. I'm happy to rewrite the script in shell, though, no big deal.

I know kvm falls back on qemu: the point is to make it easier to know whether it will or not, on a given hardware. Copy-pasting the command line from the package description works, except when it doesn't. See https://lists.ubuntu.com/archives/ubuntu-devel-discuss/2008-February/003226.html for an example.

Python is "Essential: yes" and depends on python2.5, which depends on python2.5-minimal, which provides both optparse and sys. No need for additional dependencies. I don't see the value of the script, though. kvm's init script does the detection and loads the appropriate modules or tells you if you're out of luck (i.e.: don't have the extensions you need).

The value of the script is that it makes it easy to see if your hardware supports kvm acceleration or not.

Copy-pasting the shell command from the package description has proven to not always be easy enough, see link in my previous message. If you don't think that's sufficient justification, feel free to close the bug, of course.

On Tue, Feb 05, 2008 at 11:12:00PM -0000, Lars Wirzenius wrote:
> The value of the script is that it makes it easy to see if your hardware
> supports kvm acceleration or not.
>
> Copy-pasting the shell command from the package description has proven
> to not always be easy enough, see link in my previous message. If you
> don't think that's sufficient justification, feel free to close the bug,
> of course.

Well, this script would be in the kvm package, correct? The init script
in that package already provides this check whenever it's run.

I could add a "check" option to the init script to give roughly the same
output as you suggest.. Would that make you happy? :)

--
Soren Hansen
Virtualisation specialist
Ubuntu Server Team
http://www.ubuntu.com/

I don't think running "/etc/init.d/kvm start" is as easy as running "kvm-ok" (or whatever command name you choose). It also tries to load a kernel module, which may be an unwanted side effect, but that's easily fixable by adding a new argument ("/etc/init.d/kvm check" or something).

If you add the command, you could call it from the init.d script, and centralize the checking.

Thanks for the report, Lars. I think such a utility would be useful too.

I'm attaching a debdiff that creates a /usr/bin/kvm-ok script. This script is loosely based on Lars' original. I've simplified it a bit, to a simple if/then/else statement. I strengthened the regular expression just a bit. And I removed the -v/--verbose option, as I think that's best handed by ">/dev/null" appendage by the caller, if necessary.

I dropped the script source in the debian/ dir, and install it to /usr/bin/kvm-ok. I think this should probably be pushed back upstream, if they want it.

:-Dustin

This bug was fixed in the package kvm - 1:72+dfsg-1ubuntu4

---------------
kvm (1:72+dfsg-1ubuntu4) intrepid; urgency=low

  * debian/kvm-ok: simple script to determine of the cpu supports kvm
    acceleration (LP: #188878)
  * debian/rules: install the kvm-ok binary into /usr/bin/kvm-ok

 -- Dustin Kirkland <email address hidden> Mon, 22 Sep 2008 12:09:47 -0500