The Rise of Virtual I/O

We’ve already seen the advent of storage virtualization that allows us to create pools of storage that can be accessed by multiple applications and servers. But as more virtual machines get piled on top of multiple sets of multi-core processors, I/O bandwidth is going to be a challenge.

There’s no doubt that storage companies across the landscape are zoning in on this issue. But with every major change in architecture, we’ll also see the rise of new companies pushing innovative approaches to solving this problem. One of those companies is Aprius, which early next year plans to offer an appliance that will manage virtual I/O across multiple storage arrays and various virtual machines running on multi-core processors.

According to Aprius vice president of product marketing Craig Thompson, the Aprius approach to solving this problem relies on extending the PCI Express using a custom ASIC processor deployed in an appliance that replaces the switches that normally sit at the top of the rack. Using virtual machine tagging mechanisms, the Aprius appliance will be able to keep track of application workloads and, more importantly, their I/O requirements, as they dynamically move around the network. Once the appliance determines the I/O requirements of the application, it will dynamically make adjustments across the available pool of storage.

What’s interesting about the Aprius approach is that it preserves freedom of choice in terms of the storage arrays being used. Instead of requiring an upgrade to the storage hardware to accomplish the same level of dynamic virtual I/O, the Aprius approach moves the firmware needed to manage the storage arrays into an appliance.

IT organizations with any experience dealing with the hypervisors in any of the major virtual machine platforms already know how poorly they manage I/O performance. It’s not likely that hypervisors are going to get any better at managing I/O as virtual server environments get more complex. Given that reality, the storage community is going to have to find innovative new ways to solve the problem themselves.