Windows Server to get dynamic memory with R2 SP1

Microsoft and Citrix Systems hosted a virtual desktop love-in Thursday, talking about how their respective desktop virtualization products mesh well and how the companies will continue to cooperate in the future. Microsoft also lifted the veil on upcoming service packs for Windows Server 2008 R2 and Windows 7, which have features to improve server and desktop virtualization.

If you were looking forward to a lot of detail on Service Pack 1 for Windows Server 2008 R2, which came out last fall, don't get your hopes up. Microsoft didn't say all that much about R2 SP1 for its server operating system and companion Hyper-V hypervisor. And it didn't provide any timing on when Windows Server 2008 R2 SP1 would appear.

But Microsoft did talk generally about two new features. The first and most important is called Dynamic Memory, and as the name suggests, this is a feature of Hyper-V R2 SP1 that will allow for memory on virtual machines to be dynamically scaled up and down as workloads dictate. Right now, memory is allocated statically and a Hyper-V virtual machine - and all of the software running inside of it - has to be rebooted if more memory is needed for that VM's software stack.

Dai Vu, director of virtualization services marketing at Microsoft, says that Dynamic Memory will allow for greater virtual machine density for server workloads in general and for virtual desktop infrastructure (VDI) setups in particular. By having each VM have its main memory allocated dynamically, each image will get only the memory it needs as it is running, not something approximating the peak memory needed by a particular server stack or Windows user working from a VDI setup. This means more memory is left over to host other VMs on the same box.

Vu did not elaborate on the programming behind Dynamic Memory, but did say that it was different from the memory-overcommit methodology employed by rival VMware in its ESX Server 4.0 and ESXi 4.0 hypervisors. With that overcommit, each VM and its software stack is told it has access to more physical memory than it is actually using (operating systems like breathing room, and lots of it), but each VM is only given the memory it needs as it is running. If this sounds like Microsoft's Dynamic Memory to you, join the club.

Vu was adamant, however, that Microsoft had come up with a better way and that Dynamic Memory did not "fall off a cliff" like VMware's memory overcommit can do, according to Microsoft. Microsoft did not say just how much extra VM density Dynamic Memory will allow, but you can guess the answer: that all depends on the workloads running atop Hyper-V.

The other new feature coming out with Windows Server 2008 R2 SP1 is called RemoteFX, which is virtualized graphics and media-processing capability that Microsoft picked up with its acquisition of Calista Technologies more than two years ago. What Calista was peddling when Microsoft bought it for an undisclosed sum was software that allowed server-based VDI to give end users sitting at fat or thin clients at the other end of the LAN a visual and audio experience that seemed like it was being rendered locally on a PC with a certain amount of muscle (even if it wasn't).

Well, this, of course, is exactly what Citrix has been promoting with something called HDX for its XenApp host-based application virtualization and XenDesktop VDI product. But, according to Sumit Dhawan, vice president of desktop virtualization strategy at Citrix, RemoteFX and HDX are complimentary, not competitive, technologies. Exactly how they will mesh is not clear.

What is clear is that Microsoft's Remote Desktop Services will, thanks to RemoteFX, be less clunky that it has been to date, once Windows Server 2008 R2 SP1 is announced. Microsoft says that RemoteFX will smooth out the video and audio kinks for both hosted virtual applications (App-V from Microsoft and XenApp from Citrix) as well as remote virtual machines served up from the data center (XenDesktop from Citrix, with either XenServer or Hyper-V as the back-end hypervisor in the data center).

In a blog posted by Max Herrmann, formerly of Calista and now on the Remote Desktop Services team at Microsoft, RemoteFX will allow for remote applications rendered on the server to display the Windows Aero interface, 3D graphics, Silverlight and Flash, full fidelity video, and highly synchronized audio, regardless of the target device on the other side of the Remote Desktop Protocol connection.

As part of today's announcements, Microsoft and Citrix will collaborate to allow RemoteFX to be used by Citrix' XenDesktop VDI, and that HDX will be able to sniff out when a server or an end point has RemoteFX baked in and make use of that capability. It looks like RemoteFX will be used on servers and end points working over the corporate LAN, but HDX will be used for devices hooking into virtual desktops from other networks. No word on when the HDX-RemoteFX integration will happen. Microsoft expects other partners to jump on the RemoteFX bandwagon, and indeed HP was first out of the chute saying it would make use of RemoteFX within its thin clients and server-based VDI offerings.

Citrix also today announced that XenApp 6, which was announced last week, will be rolled into the XenDeskop VDI package with Feature Pack 1. Remember, XenApp 6, which has the ability to control and serve up applications virtualized by Microsoft's App-V as well as XenApp, only runs on Windows Server 2008 R2. So if you want all the goodies in XenApp 6, you'll need to upgrade your Windows servers. (Now you see why Microsoft tolerates Citrix. Well, at least one of the reasons why.) Feature Pack 1 for XenDesktop 4 will sport faster logon and logoff for virtual desktops and support for 3D graphics for the 64-bit version of Windows 7. XenDesktop 4 Feature Pack 1 will be available on March 24.

As part of Thursday's Microsoft-Citrix VDI love-in, Microsoft said that it would add roaming rights to customers covered under its Software Assurance licensing. An existing license allowed corporate users under an SA license to have their home PC access their remote desktop image on the corporate network for $23 per device per year. Now, this is part of SA and you don't have to monkey around with the Virtual Enterprise Centralized Desktop (VECD) add-on to the SA license. This is now part of the deal. If you wanted roaming rights outside of the network firewall, you had to pay an additional $110 per Windows image to do so, and you could only do it from a Windows-based PC. With the Windows Virtual Desktop Access (VDA) add-on to the SA license, the price drops to $100 per year per device, and now that device can be anything you want - a mobile phone, an airport kiosk, Microsoft doesn't care. These SA license changes take effect July 1.

The Microsoft-Citrix VDI collaboration is also about pointing a double-barrel shotgun at VMware's View alternative to their respective products. And so Microsoft and Citrix have loaded up their products into a bundle called VDI Kick Start, mixing together the XenDesktop VDI edition and Microsoft's VDI Suite, which includes Hyper-V, App-V, and Systems Center management tools, and giving it all to customers for $28 per seat for the first year they use it. The bundle is for virtualizing 250 seats and costs $7,000, half the list price for the products, according to the two companies.

Microsoft and Citrix have also cooked up another deal called Rescue for VMware VDI, which allows companies using VMware View to switch to the XenDesktop-VDI Suite combo from Citrix and Microsoft for free for up to 500 end users.

What was missing from the mix of products and marketing, of course, is a bare-metal hypervisor for the PC itself, something that Citrix and Intel have been working on for over a year and that still hasn't come to market. Whatever happened to XenClient? Businesses want to stream hosted apps and whole PC images down to a ruggedized VM container on corporate PCs, too. ®