Windows Server 2008 R2 SP1 New Features: Dynamic Memory and RemoteFX
Microsoft has confirmed that the industry required gold standard of Microsoft stability, Service Pack 1, is in the works for Windows 7 and Windows Server 2008 R2. (Both Windows 7 and Server 2008 R2 are built on the same code base which allows for better integration, and also means that large updates like Service Packs are typically released together.)
As always, Windows Server 2008 R2 SP1 will include a rollup of patches and fixes developed since the original release shipped. Microsoft has also started banging the drum about two new features that are slated to be a part of the first Service Pack for Server 2008 and Windows 7.
New Features in Server 2008 R2 SP1 Update
The two new features mentioned in various statements and internal Microsoft blogs, such as Windows Server Division WebLog (no word on the appropriateness of the capitalized “L” in weblog) are Dynamic Memory and RemoteFX, both of which are functions for Microsoft virtualization.
Dynamic Memory in Server 2008 R2 SP1
Dynamic Memory is a new feature to Hyper-V which allows administrators to allocate all the memory available on a physical host and then have it dynamically distributed among the virtual machines that run on that host. They say that the best laid plans of mice and men often go awry. Plans for projecting how much memory a given VM may not have been the inspiration for that saying, but they certainly fit. Dynamic memory is a way to try and nudge the plans of Windows Server systems engineers back on track.
Dynamic Memory is similar to the Memory Overcommit feature in VMware that allows for greater VM density on a given set of hardware, but with a different twist. Memory Overcommit works by essentially over-promising how much RAM each VM can have. The theory is that most machines do not use their full allotment of RAM all of the time. Thus, when one virtual machine goes over its “real” memory limit, the virtual manager lets it use some of the memory that a different VM is not currently utilizing. As long as all VMs aren’t trying to use all of their allocation at the same time, there is no problem.
Microsoft has long claimed that Memory Overcommit is a dangerous solution and advocated against using it. While Dynamic Memory is very similar, the twist is that instead of fooling a VM into thinking it has more RAM than it really does, the Hyper-V manager monitors the percentage of memory being used on all the VMs and then changes the maximum amount of RAM the OS has to work with based on those percentages. The net effect is the same; more VMs can be installed on the same hardware.
The whole point of virtualization is to be able to create numerous virtual servers on a single set of hardware, or host, without having to have big reserves of hardware resources, “just in case.” By virtually allocating all hardware resources to virtual machines, IT professionals are able to maximize how costly hardware is used.
But, what happens when a formerly sleepy virtual machine suddenly becomes mission critical?
For example, consider a hypothetical cable TV channel that is typically lost somewhere “in the middle” of the channel numbers. Let’s assume that like many of its competitors this particular channel has some reality TV show starring a not-so-famous famous person when news breaks that the channel’s reality TV star backed over the Pope with his car.
The virtual machine that houses the application used to route incoming phone calls, that annoying, “Press 1 for this. Press 2 for that,” system doesn’t usually require much in the way of resources. On this day, however, it’s running full-speed when some “helpful” person reconfigures the phone lines to allow a lot more incoming call lines.
Now the VM is swamped and bogging down. If it were a submarine, the captain would be ordering Engineering to go to 105% on the reactor, but since it’s a virtual machine, it is paging everyone in IT with monitoring errors.
For even the most foolhardy server administrators, manually reallocating memory among virtual machines isn’t the kind of thing you want to do during business hours while systems are live and users are counting on those critical business systems. Without Dynamic Memory, our heroes are in a jam, having to rush through an emergency change control ticket and notifying users that some of their server-based software is about to reboot.
However, with Dynamic memory, memory is reallocated on the fly without any service interruptions, leaving our poor sys admin to deal with the sudden flood of incoming email and website traffic, instead.
RemoteFX for Windows Server 2008 R2 SP1
The other major update coming in Service Pack 1 is called RemoteFX. RemoteFX is an improvement that should help iron out some of the unpleasantness of using Microsoft Remote Desktop Services on thin clients. Essentially what RemoteFX does is handle all the heavy lifting for graphics. Rendering is done server-side and then displayed on clients without using their resources. This means that intensive effects like Microsoft Aero should start being a lot more usable on thin clients configured without a lot of hardware power.
This technology comes from Calista Technologies which Microsoft bought two years ago. Microsoft has integrated it into the session virtualization environment (Terminal Services to those of you who don’t update your lingo with every press release). Using a standard RDP connection, resource hogging multimedia presentations, full-motion video, and Silverlight animations can all be viewed seamlessly even on clients that don’t have powerful enough hardware to handle them on their own.
RemoteFX has also been licensed out to Citrix for its XenDesktop VDI, so those enterprises running these systems will be able to take advantage of this new capability as well. Citrix has been promoting HDX as a similar feature, but both companies have said that the technologies are complimentary and not competitive. Time will tell how (or if) the two will integrate.
While Microsoft hasn’t provided any details yet, they have also said that Windows 7 will get an updated RDP client as part of the Windows 7 SP1, which would allow those systems to use the feature as well. While traditional workstations wouldn’t require the feature for standard use, something like high-resolution 3-D rendering could potentially benefit from RemoteFX.
These new features show Microsoft’s willingness to roll out new technologies without a full product release or add-on pack like in the past. However, neither technology is a game changer, and just as important to those enterprises with tight change control and testing procedures, neither function makes core changes to the OS and can be disabled at install.
In the end, SP1 is what it should be, a boring accumulation of patches and a handful of improvements without any major surprises.