Side-By-Side Comparison: IIS 7.0 on W2K8 vs. IIS 6.0 on W2K3

The operations team that runs the Microsoft.com Web site is using IIS 7.0 on Windows Server 2008 to help run the site, and now it's made available a side-by-side comparison that shows how the performance stacks up against its predecessor.

In one corner: IIS 7.0 on Windows Server 2008 RTM. In the other corner: IIS 6.0 on Windows Server 2003 SP2.

During this performance assessment we found that the CPU usage was higher on Microsoft Windows Server 2008 RTM servers, which is driven by the higher number of RPS the servers were handling.  As mentioned below the hardware load balancers are sending more traffic to the Windows Server 2008 RTM servers (31% more RPS) as they are completing the outstanding web requests faster than the W2K3 SP2 server.  A good metric listed below is the “efficiency” or “cost” of the number of requests per CPU cycle (RPS / CPU Utilization %).  Using this metric, IIS 7.0/W2K8 RTM is over 10% more efficient then IIS 6.0/WS03 SP2 in handling live web platform traffic for the www.microsoft.com site.

For all the pretty pictures, including graphs and charts that back up these findings, visit the original post.