Module level variables and locking
Posted on 2002-03-27
I have a VB dll that has 10 classes. This dll gets calls from the web server(IIS). The dll is developed in VB 6.0 and runs on Win2K.
I have a common variable declared in the common module(.bas) accessible to all the 10 classes. Since the client calling this dll is going to be a web server, I am expecting a lot of simultaneous calls. This common variable is the main variable to hold the data for the classes to process the business logic. With this kind of set up of a common variable in the dll, I am afraid the response of the dll for calls to each class is going to degrade as this common variable will be mutex locked for call to each class. Am I right in thinking that the calls to each class is going to be processed sysnchronously rather than asynchronously? Is the peformance going to be affected? Should I move the common variable to the individual classes?