0

We have a new Win 2012 server hosting a legacy .NET 3.5 WCF Service (with 22 endpoints and maybe a couple of hundred operations) and we are having some performance issues and want to control the number of connections.

We have attached perfmon Web Service/Current Connections counter and see this value repeatedly rise to a steady 24 connections (with occasional spikes to 25).

Perfmon view showing Current Connections

We have tried managing the number of connections using system.ServiceModel\behaviors\serviceBehaviors\behavior\serviceThrottling. We have tried default values, low numbers, recommended and high numbers:

<!-- default --> 
<serviceThrottling />

<!-- low --> 
<serviceThrottling maxConcurrentCalls="5" maxConcurrentSessions="10" maxConcurrentInstances="15"/>

<!-- recommended (2 processors) --> 
<serviceThrottling maxConcurrentCalls="32" maxConcurrentSessions="200" maxConcurrentInstances="232"/>

<!-- high--> 
<serviceThrottling maxConcurrentCalls="2000" maxConcurrentSessions="2000" maxConcurrentInstances="2000"/>

enter image description here

  1. Where else might this connection limit be getting set?
  2. Have we added the correct counter in perfmon?

Update

We've added another client, and doubled the number of requests that the WS server is processing. So this has proved that the throttling is occuring upstream. The upstream client is a .NET3.5 ASP.NET website. The connection to the WCF service is via a wsHttpBinding.

We have already added system.net\connectionManagement\maxconnection and this hasn't had any impact.

What other settings might throttle outgoing ASP.NET connections to a WCF service?

Mark Cooper
  • 6,738
  • 5
  • 54
  • 92

1 Answers1

0

please try adding this section and test the performance again:

  <system.net>
    <connectionManagement>
      <add address="*" maxconnection="250" />
    </connectionManagement>
  </system.net>

the default value is 2.

Mohammad
  • 2,724
  • 6
  • 29
  • 55
  • I already had this setting in the client, but have now also added this to the WCF service too. The `Current Connections` has now jumped temporarily to 34 and then settled back to 24 again. I don't think this has helped, but thanks anyway. – Mark Cooper Nov 15 '16 at 13:11
  • This makes me feel like this is a connection limit on an upstream service? We using Jmeter to apply load via a website and I am running 120 threads on there. – Mark Cooper Nov 15 '16 at 13:25