Question

I have an IHttpHandler which I believe can benefit from re-use, because it is expensive to set up, and is thread-safe. But a new handler is being created for each request. My handler is not being re-used.

Following is my simple test case, without the expensive setup. This simple case demonstrates my problem:

public class MyRequestHandler : IHttpHandler
{
    int nRequestsProcessed = 0;

    public bool IsReusable
    {
        get { return true; }
    }

    public void ProcessRequest(HttpContext context)
    {
        nRequestsProcessed += 1;
        Debug.WriteLine("Requests processed by this handler: " + nRequestsProcessed);
        context.Response.ContentType = "text/plain";
        context.Response.Write("Hello World");
    }
}

Requests processed by this handler: 1
Requests processed by this handler: 1
Requests processed by this handler: 1
Requests processed by this handler: 1... at least 100 times. I never see > 1.

Am I misunderstanding how IsReusable works? Is there something else that can defeat re-use? My handler is being called from a Silverlight application if that makes any difference.

Answer 1

IsReusable is not a guarantee.

Just refactor your handler and put all cross-request state into a different class. Clearly separating cross-request state in a web application in best-practice anyway because it is dangerous.