WCF 4: Default Throttling Settings for WCF Services

Question

I was reading Wenlong Dong's blog article about the default throttling settings for WCF services in WCF 4, and have a question about the values for the default settings:

MaxConcurrentSessions: default is 100 * ProcessorCount

MaxConcurrentCalls: default is 16 * ProcessorCount

MaxConcurrentInstances: default is the total of the above two, which follows the same pattern as before.

Does ProcessorCount refer to:

1. The number of physical CPUs/sockets
2. The number of physical cores across all CPUs
3. The number of logical cores, if hyperthreading is enabled?

Thanks,

-- Patrick

Answer 1

Processor count means logical cores. The value is actually the value supplied by System.Environment.ProcessorCount

Answer 2

Here are some stuff from MSDN that might be helpful. Optimizing WCF Web Service Performance: http://msdn.microsoft.com/en-us/library/ee377061(v=bts.10).aspx

ServiceThrottlingBehavior Members: http://msdn.microsoft.com/en-us/library/system.servicemodel.description.servicethrottlingbehavior.maxconcurrentsessions(v=vs.100).aspx

http://msdn.microsoft.com/en-us/library/system.servicemodel.description.servicethrottlingbehavior_members(v=vs.90).aspx

Cheers