Intel 7400 manual Introduction - Can We Virtualize Everything?, “Non-virtualizable” applications

White Paper Consolidation of a Performance-Sensitive Application

Introduction — Can We

Virtualize Everything?

Virtualization of enterprise data center applications using hyper- visors or VMMs is taking a predictable path. It started with the consolidation of the simplest, least performance-sensitive, and least mission-critical applications, many of which had hardware utilization figures in the 10 percent or less range. These applica- tions were the “low-hanging fruit” of the first wave of applica- tion virtualization, and consolidation ratios were quite high while still delivering adequate performance. This consolidation wave delivered a significantly positive ROI to the organizations. IT organizations would like to have the benefits of virtualization across the entire spectrum of applications, but there are challenges to delivering on this potential.

“Non-virtualizable” applications

Not all enterprise applications fit the description above, of course. There are more complex, high-performance, and mission-critical applications, too. Many of these applications are very demand- ing of the hardware resources in state-of-the-art servers; there- fore we expect that it would be more difficult to virtualize them while retaining adequate performance. Examples of some of the generic types of applications that don’t fit the “low-hang- ing fruit” description are those characterized by the following characteristics:

•Mission critical

•Transaction latency sensitive

•Cpu intensive: single thread vs. multi-thread

•Memory intensive: size/throughput/latency

•I/o intensive: disk/network; throughput/latency

From our experiences with virtualization we know there are certain overheads involved with delivering the value that a VMM/hypervisor provides. These overheads can impact all the characteristics noted above. This leads to the perception that these types of applications “can’t be virtualized” because the tradeoffs would be too severe. Is this a perception or reality?

ESL

Electronic Sports League (ESL) is the largest online gaming community in Europe, with more than 844,000 active users as of August 12, 2008.

ESL has deployed thousands of game servers to provide services to its members. Obviously, for a game services company, the game servers are mission critical. The key performance criterion measured by gamers is the in-game transaction latency, which determines the responsiveness of the game and is a key component in the competitive edge for the players, many of whom are actually profes- sionals and quite demanding of the performance of this key criterion. In addition, most game server code is single- threaded and very CPU intensive, with CPU utilization typically in the 60-80 percent range.

Internet

Firewall

Game Servers

Figure 1.. ESL game server high-level architecture..

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