Just two days ago Brian Madden published a very provocative analysis of the Citrix positioning in the virtualization industry, claiming that the current market share for XenServer is near zero and predicting that the company will eventually drop the open source engine in use, Xen, in favor of the just released Microsoft Hyper-V. And this would imply a shift of the community from Xen to KVM.
(virtualization.info covered the Madden analysis and many others in a very long article titled Microsoft Hyper-V: the day after)
Obviously, this prediction created a wide reaction and so far virtualization.info collected some feedbacks from readers believing that the scenario is perfectly possible.
Simon Crosby, CTO of Virtualization & Management Division at Citrix, spent a long post to answer to Brian Madden on all the points.
On the Citrix market share:
We have somewhere approaching 4,000 enterprise customers, and about 3000 trained channel partners. VMware claims 100,000 customers. Citrix has about 220,000 customers and about a hundred million users. The XenServer market share is small, and growing as rapidly as any such product can given the current VMware brand status, and the fact that we started well behind them. We had a few key blockers for enterprise adoption, four fifths of which are addressed in our forthcoming XenServer 4.2 release.
On the drop of Xen:
It is important to state yet again that we are not in a competition for server sockets with Microsoft. If that were the case, why would we have helped Microsoft to make Hyper-V a better hypervisor, by developing the shims and drivers that will allow Linux to run with optimal performance on Hyper-V? The founding thesis of XenSource, and the continued strategy at Citrix, is to promote fast, free, compatible and ubiquitous hypervisor based virtualization. If the hypervisor is free, why worry about who delivers it?
On the community shift to KVM:
It’s just a VT/AMDV driver added to Linux to allow it to host additional VMs. Great if your usage model is “first install Linux, then use your Linux skills to install VMs”. Unfortunately it doesn’t address any of the other key requirements for virtual infrastructure (virtualization-aware shared storage, snapshotting, cloning, thin provisioning, HA, and much more) it is just another way to do basic CPU and memory virtualization … at a time when Xen already offers Linux a typical overhead of under 1% (SPECJBB), and a rich set of value-added features.