I have just set foot on the ground for the annual Citrix analyst event in Dallas, TX, and in the next couple of days I'll hope to make a call on what the future will hold with Citrix. Does the Citrix of tomorrow have more or less relevance in the virtual infrastructure? This year, as in years past, I see tons of potential for more, but time, and this event will tell. The potential resides in Citrix being more about the sum of the parts than the parts themselves - in fact, Citrix is really a sum specialist, whether it is about summing their own stuff or somebody else's. Put in another analogy, they are specialists in glue, and I'm waiting to see if they're ready to open up the bottle.
Citrix is no slouch when it comes to delivering unique "glue" between different layers of the infrastructure. Just for context, their glue experience reaches all the way back to the early days of Server-based Computing where they largely started out as compute across remote access links, and Citrix tenaciously differentiated and held on to that market despite huge disruptions. Taking this analogy to the extreme, you can look at almost any Citrix product and think of how it glues together various parts of connections, infrastructure layers, management systems, or workloads to overcome the challenges of delivering compute experiences - NetScaler, WANScaler, XenDesktop, and more. Even the latest example of Citrix's StorageLink has been about better "gluing" together storage systems and virtual machine storage, and I've talked with users realizing better storage alignment, and preservation of their existing practices by running StorageLink. I have no doubt that Citrix is seeing some uptick in adoption from customers trying to virtualize while preserving their previous practices and technologies, or trying to meet some unique needs outside of generalized virtualization. If such customers are looking deeply enough, they likely realize that Citrix may have some differentiation in gluing together a whole stack of compute experience from a virtualized desktop all the way down to the storage layer, or in integrating other specialized services into a cloud-like infrastructure.
To date, we've continued to see some upticks in XenServer adoption (great article here courtesy Beth Pariseau)
, but the future still looks cloudy for general Xen adoption when measured purely against competitive hypervisors. The problem is, when the Xen hypervisor still seems to be at a disadvantage when it is considered in isolation. Recent testing
(warning, the link goes to a PDF of the report) with ESXi, Xen, KVM, and Hyper-V by Taneja Group suggests that the ESXi competitors simply have a long way to go in density and performance; mostly from lack of sophisticated memory virtualization mechanisms. In point of fact, RedHat made a good demonstration of how Kernel Samepage Merging alone can extend overhead without pure performance eating paging out of physical memory - but they were the only competitor to demonstrate what I would call a sophisticated memory mechanism.
So I've been asked of late, given Taneja Group's recent work in evaluating hypervisor performance, and the disparity we reported on among saturated performance capabilities, how can I continue to see a good future for this company that seems to be all about Xen? That gets back to Citrix being about the sum, rather than the parts. Citrix has turned Xen into their platform for gluing things together - with the glue being about how the parts are pulled together - and the construction paper this go around is more about the data center and clouds. In fact they've made good progress turning Xen to this purpose of the past 2 years, and Citrix has great cred here - even the albeit customized Xen foundation behind Amazon EC2, to the foundations behind the fast up and coming Amazon competitors like Rackspace. Moreover, we're reminded periodically about the tremendous merits of open - IBM announced some potentially cool workload orchestration on an open hypervisor
the other day (although given the level of supporting detail, I'm tempted to call horse hockey). And beyond cred, Citrix has great cards on the table in their other virtual and physical infrastructure technologies. But the cards too often remain unexposed, or only flipped up one at a time. If the audience is the cloud, they're paying attention, and it's time to show the cards, and not just in a private room off to the side of the parlor: network management well beyond the hypervisor edge, integration with the surrounding infrastructure, an integrated stack through compute service access to workload hosting, instrumentation, and more. But I recall saying similar things 2 years ago.
But nevertheless, for the practitioner, despite the visibility of the messaging, one of the things that any visit with Citrix shows us, is it's worth considering what your total infrastructure looks like with virtualization as a key part of the foundation. There's still lots of stuff outside the boundaries of the virtual server infrastructure, and virtual infrastructure innovation is equal parts about how to integrate with that stuff. The vendors can paint distinctly different pictures. We'll see some more differentiators pop up over the next year or two, but undoubtedly the differentiators will narrow in degree and number over time. For vendors, today is the day to be competing on those differentiators, especially when they show up in important markets like cloud.