What is the limit of concurrent call to a service on TCP with reliabalesession TRUE?

Question

What is the limit of concurrent call to a service on TCP with reliabalesession TRUE?

Answer 1

That depends on your service throttling settings, and on whether or not you're using sessions.

By default, the server is limited to 16 concurrent calls, and a maximum of 10 concurrent sessions. But this is a server-side setting which can be tweaked.

<behaviors>
  <serviceBehaviors>
    <behavior name="ServiceThrottling">
      <serviceThrottling
          maxConcurrentCalls="16"
          maxConcurrentSessions="10"
          maxConcurrentInstances="20" />
    </behavior>
  </serviceBehaviors>
</behaviors>

If you do have reliable sessions set to true, you're most important settings are "maxConcurrentSessions" (how many sessions = clients can be connected at any given moment), and "maxConcurrentInstances" (how many instances of your service object can exist at any given time).

Try to set everything to e.g. 20 or so and see how your system behaves. How are clients calling in? Anyone getting rejected? How's the load on your server? Can it handle those 20 callers just fine, or is it almost dead from exhaustion? Tweak your settings accordingly (up or down).

Marc