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Gartner's Chris Wolf Talks About Citrix

As they always do, Chris Wolf's cutting-room-floor comments from our recent interview about VDI went over big with readers, so I am offering more of his views and opinions below.

Today's topic is Citrix, and he begins by responding to my question about the company being well placed with both their hosted server desktop and VDI strategies.

“Yes, I mean they're number one right now in terms of market share by our numbers. They're making all the right moves. I do think that when you look at features specifically like IntelliCache, they're really important to customers and IntelliCache has been one of the drivers behind their really big upswing in terms of XenServer getting in the data center behind XenDesktop workloads. So IntelliCache is one reason, and cost is the other. If you look at the vSphere 5 licensing, for example, it's a subscription license that's $60 per user per year for vSphere to sit behind XenDesktop.

"But if we get back to IntelliCache, this has been one of the real big capex challenges of storage for virtual desktops. I've seen this literally play out well over 100 times in inquiries with different end-user organizations, and that is they deploy virtual desktops on persistent network storage, they start to scale the environment, they start running into some boot storm problems, and then the first thing that happens is the storage vendor gives them some SSD storage at the front of the array to cache some of the I/Os and hopefully solve that challenge.

"That typically is not enough, and then they wind up looking at other third-party offerings like Fusion-io or Atlantis Computing to give them even more local caching. Now, the thing you run into here--and what folks figure out along the way--is they're taking this shared virtual desktop boot image that's effectively a read-only file, putting it on network storage, and then at the end, winding up having to install local storage on their servers so they can locally cache the thing.

"What a lot of customers say is, 'Well, why don't I just store it locally in the first place? Why do I need all this extra, expensive, third-party storage hardware overhead?' A lot of times, the answer is, 'Well technically you don't.' In the case of Citrix with the IntelliCache feature, that's specifically the problem they solve, and it's something that's included with the hypervisor.

"In the case of VMware environments, you kind of have to go with some of these third-party solutions because while ideally I would like to have that boot image stored locally for performance's sake, it's not always that practical because I can't manage the consistency of that image file across all of my physical server nodes.

"Citrix has been at this a very long time--15 years or even longer of building out an infrastructure platform. When it gets down to bells and whistles, Citrix is going to win every time just because of the maturity of their solution."

Posted by Bruce Hoard on 02/17/2012 at 3:46 PM


Reader Comments:

Wed, Feb 22, 2012

Always good to hear Chris's view on VDI from real world customer engagements. Pretty damning for VMware if you read between the lines above. CBRC will deliver similar capabilities to Intellicache with XenServer to vSphere and could remove the need for that additional SSD layer in the SAN to deal with the high reads at boot storm. The likes of Fusion and Atlantis - although they do fundamentally different things - both enable the removal of shared storage for VDI with stateless desktops which dramatically reduces costs. I'v recently seen the Atlantis solution in a colleagues VDI environment and I'm now favouring that over Fusion for a couple of reasons: - 1. They can deal with both stateful and stateless desktops using both local and shared storage 2. They are able to serve all reads from RAM (faster than SSD in shared storage) and also process the writes before they hit storage - we are seeing 75% writes in our environment and it is the write peaks (AV and SCCM etc) that are killing our storage rather than the initial boot storms. 3. They are software rather than hardware and don't require any changes to the guest OS. I'm planning to start a POC with ILIO over the next few months to assess the impact it has on our environment. It will be interesting to see how the ILIO read cache compares to CBRC - aiming to test that at the same time.

Tue, Feb 21, 2012

Expect to see Content-Based Read Cache (CBRC) enabled in VMwareView 5.1 which will somewhat reduce the need for 3rd party host-based caching tools.

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