Performance tips

Keep the following in mind when deploying the Relay Server to Microsoft IIS on Windows:

  • The Relay Server web extension does not rely on ASP.NET. Removing the ASP.NET ISAPI filter yields better performance. The filter gets turned on by default in a standard Microsoft IIS install. To turn off the filter, do the following:

    1. Start Microsoft IIS Manager Console.

    2. Edit the properties of Default Web Site.

    3. Under the ISAPI Filters tab, remove the ASP.NET filter.

  • For better performance, you can turn off the Microsoft IIS access log. To turn off the access log, do the following:

    1. Start Microsoft IIS Manager Console.

    2. Edit the properties of the ias_relay_server directory under Default Web Site.

    3. Under the Directory tab, clear the Log Visits selection.

  • In a production environment, Relay Server verbosity can be set to 0 via the Relay Server configuration file. This yields better performance under high loads.

  • The Relay Server does not impose restrictions on the Web garden size. One worker process may serve requests from all Outbound Enablers as well as from all the clients. However, the number of threads that can be created in the process is limited by the process heap space left available for thread creation. The thread created by Microsoft IIS has a 256k stack size. If your computer has adequate resources, experiment with a higher number of processes if you suspect you are hitting a concurrency limit when the server is loaded with thousands of concurrent requests.