Tin foil hat time!
"1 - not much room here for technical arguments, but if you want an enterprise-level hypervisor the options are Vmware and Xen: Citrix Xenserver, VirtualIron, Sun SVM, Oracle Virtual Machine and Amazon EC2 are all Xen. No KVM."
What I know about enterprise-level hypervisors you could write on the inside of a matchbox without taking the matches out first, so I'll take your word for it. I thought we sold something which was effectively equivalent to a KVM hypervisor, though.
"2 - Not sure what you mean about the money. RH paid $107M for Qumranet (ie. KVM), then started dropping Xen. Coincidence? I don't think so. The $107M is doing the talking, and it says that RH wants to move into commercial virtualisation, and it wants to differentiate itself through KVM, and not by simply using the more mature (and GPL'ed) Xen."
What I meant was that when you start throwing around phrases like 'money talks' you're usually talking about corruption, and that, as I said, works the other way around. It wouldn't be Red Hat *spending* money and changing its approach to something as a consequence: it'd be someone else *paying Red Hat* to change its strategy. Imagine if, for instance, Qumranet had stayed independent but had made a $100m 'donation' to Red Hat, after which all the things you noticed had happened; *that* would be 'money talking'.
"3 - So, how many of the people who are paid to work on virtualisation at RH actually came from Qumranet? And how many of them run datacentres, as opposed to just developing the product?"
I don't know. I imagine, to make you happy, the answers would be 'most of them' and 'few or none', though I have no idea how extensively we use virtualization internally.
"4 - the Dom0 support in Fedora has never had problems (no more than anything else, anyway). That's why I (and lots of other people) are still on F8. The issue is that Fedora *unmerged* Dom0 support in F9. This was crazy - why? You don't need to be a conspiracy theorist to see RH's commercial interests behind this. Anyone using Fedora post-8 now relies on third party RPMs."
Well, you kind of do, because taking capabilities out of *Fedora* really doesn't help Red Hat's commercial interests a whole lot; as your post indicates, it's not like we have people locked into Fedora in some way, you can happily just go run SUSE. AIUI the reason dom0 support got de-merged is rather more boring: it's a huge patch that's painful to maintain and it became clear it wasn't going to get upstreamed.
There is a Fedora feature for restoring dom0 support, BTW - http://fedoraproject.org/wiki/Features/XenPvopsDom0 (which as you can see from the page name is about the pvops stuff). I think it was targeted for F13 / F14 for a bit but for some reason it turned out not to fly.
I dunno, I guess most of what you're saying is pretty much true: Red Hat started off being quite favourable to Xen and after a while we definitely moved over to a strategy based on KVM. Anyone with eyes can see that. But it's just the idea of 'money talks' that doesn't seem to fit in here, to me anyway. So we bought Qumranet; I mean, yeah, but the whole *point* of that is that someone in RH looked at Xen and KVM and decided KVM looked like a better idea, and then the corporate strategists or whoever decides these things figured the best way to pursue a KVM future would be the Remington strategy (we liked it so much, we bought the company). I suppose the only 'conspiracy' angle would be if we decided to buy Qumranet first and then forced KVM on an unwilling public to prop up Qumranet, but why would we do that? It wouldn't make any sense. KVM *was* Qumranet; it doesn't make any sense to spend a ton of money buying the company unless you actually think KVM is awesome and want to work with it anyway. The only other 'evil RH' angle would be if RH was actively stopping Fedora contributors from implementing Xen dom0 support, but AFAIK we really aren't. It's just that the engineers who maintained the dom0 patch for Fedora before were RH engineers and RH doesn't want to do that any more. That's RH's right, after all.