If you want to continue the discussion throughout the rest of the “blogosphere”, post articles on your own sites and just trackback to this one.

Thanks for joining in the discussion.

Indeed, the comparison to which I was witness did exclude the XenServer dom0, which is what I pointed out. Your comparison–Xen hypervisor vs. VMkernel + VMM–is indeed much more accurate, fair, and a valid comparison to use.

Of course, the flip side of that is the fact that VMkernel + VMM can do things that Xen hypervisor can’t do. So some–perhaps not all–of the difference in size (and complexity) is justified.

With regard to support for paravirtualized kernels, that functionality is shipping in ESX Server 3.5, unless I am mistaken.

I can’t speak to VMware’s ability to run enlightened Windows Server 2008, so it sounds like you may have an edge there over VMware.

Again, thank you for your honest and forthright discussion.

As for paravirtualized Windows — we’ve made it known that we plan to run enlightened Windows Server 2008 at some time. Obviously, we don’t do so now. Will VMware?

If that’s what we ever actually said, it would indeed be unfair.

But that is NOT the comparison we make, and never has been.

The actual comparison is that (XenServer hypervisor) is much smaller than (VMware vmkernel + VMM) — that is, that the code for all the special-case emulation makes it huge and requires an army to support and enhance it, while Xen’s reliance on paravirtualization and hardware assist takes most of that complexity out.

Have them send you an engineer, not a salesman, and not a sales engineer.

One of our vendors, after a couple se meetings, I asked if they would just send me an engineer, and they agreed. After two meetings, I told them never to send a salesman again. I’ve been hooked on this procedure every since. Works a treat!

It’s happened to all of us, from all vendors, at one time or another. There’s a lot of hyperbole out there, from all sides, as vendor vie for the business. I’m just trying–unsuccessfully, it seems–to get down to the facts.

Thanks for reading!

I’m part of the three-person team who initially brought up 64-bit VMs on AMD hardware before SVM in 2004, and I am the one person team who brought up 64-bit VMs on Intel hardware with VT in 2005.

…When Xen Source sales people try to sell Xen by …

Oh, and Simon, you really need to stop with the “we haven’t shipped hotfixes” statement. Reading is fundamental: http://forums.xensource.com/ann.jspa?annID=14.

I leaned over in a meeting and whispered to the Hitachi rep to stop smearing IBM just the other day. He used the easy ambush, unfortunately I know IBM’s kit pretty well, so I gave him the polite warning. He did not repeat the mistake, and we parted on good terms. If anyone is from HD, please keep in mind that MOST storage vendors have some type of PFA…It’s rude to trot out what is a basic block of most vendors repertoire as if you are the only one that does it….

Most SE’s take the competition too seriously and end up annoying customers. I have dismissed more than one vendor because they couldn’t seem to curtail their constant “betterness” than a competitor. I lose patience quickly in such instances, because most of the time I know both products already, they’re simply there because it’s procedural.

That said, I have used both, and I administer a rather large installation of ESX(and further, I am an experienced citrix tech to boot). You would do better to leave out the portions of the pitch he mentioned. He’s obviously more patient than some of us. I would have asked you why you were not comparing size with 3i(where the add on is removed), and when you threw your second(and for me last) strike stating you can’t cold migrate between chip vendors, I would have politely asked you to leave. You have to know BOTH systems before you start comparing them, or you end up with egg on your face, and a lost sale.