Solving the Thorny Issue of QOS in Virtualized Applications

Solving the Thorny Issue of QOS in Virtualized Applications

Porting existing applications that reside on a traditional physical infrastructure to a virtualized environment in the cloud sounds like a great idea, but the reality is that shifting apps to the cloud may come with a decrease in application performance. Ensuring quality of service of those applications is important to keep them running at expected levels, which in turn keeps productivity up.
According to Zohar Gilad, executive vice president of Precise Software, the key component to ensuring quality of service to virtualized applications is automation. The most common applications being ported to the cloud right now are second and third tier apps, the non-mission critical business apps like web servers, print servers, etc. Making those applications virtual will offer the business cost savings and more agility because it’s easy to provision virtual servers, but if those applications aren’t functioning at previous levels of efficiency, was it really worth it to make the move to a virtual infrastructure?

“What happens when you move from physical to virtual infrastructure [is] most of the old problems that presented applications to scale gracefully has now gone away,” Gilad said. “All the old problems are still here. As with any new computing platform, you have a new set of issues.”

There are three main problems associated with applications in virtualized environments:

1. The problems of a traditional infrastructure don’t suddenly go away.
2. Degradation of quality of service during and after the transition to virtualization.
3. Inter-application shared resource contention can degrade performance.

Michelle Warren, president of MW Research and Consulting, degradation of application performance when software is moved to virtualized environments is something that organizations are worried about right now.

“And the reason it depends is software is really tricky, and to be able to do one thing and one program, users tend to think we can do it in another program,” Warren said. “There’s this belief that everything’s straightforward, but in reality, in the background it’s very complicated. They’re complex environments.

The slightest change reaches down through the application, so porting something into a virtualized environment is just fraught with the ability to add complexities and change the way it looks, change the way users interact with it and the way it interacts with other programs.”