As a quick preview of the Exchange 2010 on vSphere work that I am doing I put together this blog post to talk about the CPU utilization of the various server roles. Exchange 2010 changes things a bit and now that the Client Access Server (CAS) role is now more involved several people have asked me about the impact.
I have tested across a wide range of memory configurations with a few different vCPU configurations with Exchange 2010 on vSphere. In a future post on VROOM! I will go into all the details of those tests. Here I'm just going to show the CPU utilization with 1000, 2000, 4000, and 8000 users. Regardless of the number of vCPUs or RAM assigned the CPU utilization stayed within a very narrow range for given number of users for the Mailbox, CAS, and Hub Exchange 2010 server roles. The table below shows the average CPU utilization for the number of users, with each vCPU equal to 100. So a 2vCPU VM would max out at 200 and a 4vCPU VM would max out at 400. This is the same way that esxtop reports CPU usage, which is what these numbers were gathered with. The results show a linear increase in CPU usage across all three roles:
Number of Users | Mailbox | Hub Transport | Client Access Server |
1000 | 28 | 5 | 13 |
2000 | 52 | 9 | 24 |
4000 | 98 | 25 | 47 |
8000 | 205 | 54 | 91 |
The LoadGen 2010 beta VeryHeavy User profile with 100MB mailbox size was used for these tests. The system the tests were run was a Dell R710 with 2x Intel Xeon x5570 quad core processors.
