Windows Server 2012 and Windows Offloaded Data (ODX)

Recently, while working on optimizing a Hyper-V system used mainly for development and testing work, I ended up investigating something called Windows Offloaded Data, or ODX. The purpose of ODX is simple: to let two networked components share (copy) data directly between each other, instead of using a third component or computer in between.

Say, you have a normal Windows network with two servers and your own machine, such as a laptop over WiFi. Traditionally, if you copy data using your own computer from \\SERVER1\SHARE to \\SERVER2\SHARE, you are in fact copying data first from Server1 to your machine, and then onwards to Server2. Of course, if your network is large and/or your own computer has a slow connection (as WiFis often are), you are just slowing the copy operation down.

Enter ODX. With select enterprise hardware, newest OS versions (Windows 8 and Windows Server 2012 or later) and specifically when copying files that match the rules, you can strip your own machine out from the equation, usually resulting in much faster copy operations, perhaps using 10 gigabit Ethernet (common nowadays in server rooms) or even fiber.

An interesting piece of technical details is that the new ReFS file system isn't yet supported. But then again, NTFS is probably the most common file system in use.

If you are writing something like backup applications, be sure to investigate ODX. Sounds like a great performance gain to get that working for copying your Hyper-V virtual machine files, for instance.

Happy hacking!