Although counterintuitive, it turns out that virtualization can actually improve the performance of some web hosting applications. Major chip maker AMD found that overhead caused by virtualization doesn’t always cause performance hit.

VMware, A big player in the virtualization industry, has worked closely with Intel and AMD to get the most of virtualization extensions integrated in current multi-core processors. AMD, for example, has been experimenting with an open-source caching system called Memcached that can be implemented in large cloud-based services, including Twitter, Youtube, WordPress and Digg. Memcached can speed up server performance by taking the load off back-end databases.

Unfortunately, there is an issue with Memcached and that really comes down to the fact that Memcached is quite old by current Web hosting standards. The service was developed in 2003, when web hosting industry still employed mostly single-core servers. In its original form, Memcached is thread-limited and its performance can hit a brick wall when it needs to work with 4-6 threads. A thread-limited caching system can bring problem for web hosts that repeatedly need to scale up their infrastructure due to increased workloads — simply chucking in more processors won’t help. This is an especially vexing issue for AMD, because its business revolves around selling more and more processors to the customers. And this is where server virtualization comes into play.
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