Released: Exchange 2013 Server Role Requirements Calculator Update

This is great, this update will be helpful for our Exchange 2013 CU3 On-Premises deployment project.

Thanks Ross :-)

I'm glad to see the CPU % requirements estimation has been reined in a little bit from the previous 5.9 calculator! :-)

I take that back, I must have fat fingered the data input my first try.

Our same user messaging profile in 2010 takes 20% CPU utilization on our 8 core SPECInt2006 rated CPUs of 251, and in Exchange 2013 the exact same configuration (user messaging profile, DAG configuration, etc) takes 111% CPU utilization.

Thats a 500%+ increase in CPU requirements and we had hoped there was a mistake in the calculator math because while we understand there is more work going on the mailbox role in 2013 (hub transport is integrated, multiple STORE worker processes now, database page compression, etc...) that seems excessive.

This calculator is going crazy, it gave 155 TB storage  requirement for 2500 seats. 2 servers with 4 Active DB each on Production Data center and having the same number of servers on DR site.

Ross,

I am getting some really wacky results that make no sense. When I plug the exact same numbers into both the Exchange 2010 Calc and this new 2013 Calc it tells me I need 50-100% more CPU resources depending on the numbers I put in.

If this is correct, then it appears Exchange 2013 requires at least 50% more CPU resources than Exchange 2010 to run the same number of users. Is this correct...and why?