Optimal number of cores

[KyleDixon]

At the 2012UC in the Enterprise GIS Architecture session the speaker said that adding additional cores past 4 gave less performance gain per core.

The only reference I can find is here:
http://blogs.esri.com/esri/arcgis/2011/02/17/arcgis-server-virtualization-dos-and-donts/

Is there any more information available on performance of multiple cores?

[KyleDixon]

We are using Windows Server and ArcServer 10.1

[nicogis]

see http://wiki.gis.com/wiki/index.php/Server_Software_Performance
http://wiki.gis.com/wiki/index.php/System_Design_Process