Forcing asmx web service to handle requests one at a time

Question

I am debugging an ASMX web service that receives "bursts" of requests. i.e., it is likely that the web service will receive 100 asynchronous requests within about 1 or 2 seconds. Each request seems to take about a second to process (this is expected and I'm OK with this performance). What is important however, is that each request is dealt with sequentially and no parallel processing takes places. I do not want any concurrent request processing due to the external components called by the web service. Is there any way I can force the web service to only handle each response sequentially?

I have seen the maxconnection attribute in the machine.config but this seems to only work for outbound connections, where as I wish to throttle the incoming connections.

Please note that refactoring into WCF is not an option at this point in time.

We are usinng IIS6 on Win2003.

@Alex: Did any of these answers help you? You should upvote the ones that helped, so people reading this question later will know which are the helpful answers. — John Saunders
Not really. I am looking for details on how IIS6 behaves (or can be forced to behave) in this scenario. Programmatic solutions are no good to me in this case, and I can not upgrade to IIS 7. — Alex
IIS has nothing to do with the problem. It is not involved except to pass the requests to ASP.NET. — John Saunders
So, given that changing the behavior of IIS6 cannot solve your problem, is is possible that one of these answers will solve your problem? — John Saunders

John Saunders John Saunders · Accepted Answer · 2009-06-01T13:09:14

What I've done in the past is to simply put a lock statement around any access to the external resource I was using. In my case, it was a piece of unmanaged code that claimed to be thread-safe, but which in fact would trash the C runtime library heap if accessed from more than one thread at a time.

Forcing asmx web service to handle requests one at a time

3 Answers