gpg: failed to create temporary file '/var/lib/lurker/.#lk0x57971100.hantslug.org.uk.10957': Permission denied
gpg: keyblock resource '/var/lib/lurker/pubring.gpg': Permission denied
gpg: Signature made Wed Jul 15 14:18:53 2009 BST
gpg: using DSA key 20ACB3BE515C238D
gpg: Can't check signature: No public key
On Wed, Jul 15, 2009 at 01:40:07PM +0100, Adam Trickett wrote:
> On Wednesday 15 Jul 2009, Hugo Mills wrote:
> > On Wed, Jul 15, 2009 at 12:58:34PM +0100, Adam Trickett wrote:
> > > KVM is interesting, it's in the mainline kernel and Xen is
> > > not. The firm behind KVM is now part of Red Hat and the firm
> > > behind Xen is Citrix (a big Microsoft partner).
> >
> > There's quite a lot of Xen support in the kernel. It's not all in,
> > and there has recently been a big argument on the linux-kernel list
> > about the proposed changes for dom0 support.
>
> I thought as much, I knew Xen as big and there were a lot of arguments
> last year. I know that KVM went in quite quickly, I believe it's very
> simple.
There's also quite a lot of chatter about KVM on linux-kernel:
rather more than about Xen (although I may have missed Xen-related
things because I don't know the people's names as well). This would
indicate that the KVM developers are much more actively engaged with
the kernel community, which is usually a good sign.
> > > The userland part of KVM is mostly Qemu which is pretty mature
> > > already
> >
> > Xen also uses qemu for its device emulation.
>
> Is there any VM solution that doesn't use Qemu? I gather VirtualBox uses
> bits too.
I don't think VMWare uses it. All the others that I'm aware of do,
because it's a good, reliable and tested codebase for emulating PC
platform hardware (and, indeed, a range of non-PC hardware).
[snip]
> > I've used Xen, VMWare, KVM and (k)qemu on various systems in the
> > past. Of those, Xen was by far the hardest to get going sensibly.
> > I've had some issues with VMWare not keeping their kernel module
> > sources up to date with the latest kernel, requiring patches. kqemu
> > didn't like running 64-bit guests on 64-bit hosts last time I tried
> > (and when I reported the problem, got told to get out my debugger and
> > get to work).
>
> My only gripe with Qemu is that at every significant upgrade, Windows NT
> class clients refuse to boot because of subtle emulation changes. Linux
> systems seem happy to keep running though.
>
> As far as I can tell a single Qemu disk-image can run under Qemu/kqemu
> or KVM without modification which seems like a good idea to me. It's a
> pity that VirtualBox can't use Qemu "Qcow" disk-image files directly.
There's been some issues I've heard of with data corruption on qcow
images recently. I don't recall the details, as I always use raw block
devices instead, so I've not encountered it.
Hugo.
--
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
PGP key: 515C238D from wwwkeys.eu.pgp.net or
http://www.carfax.org.uk
--- Hey, Virtual Memory! Now I can have a *really big* ramdisk! ---
