Parallel invokation of non reentrant native function using JNA

Question

I'd like to parallelize calls to a native library (DLL) that is not reentrant. Two threads should call the native function in parallel. I want to use JNA to access the DLL. Locks are not a solution since this is not parallelism.

My thoughts until now:

• Thread pool with threads holding each a Proxy instance to the DLL loaded with Native.loadLibrary() (it might only work if the DLL can be loaded multiple times in one JVM and do not share any state)

• Thread pool with threads holding each a Proxy instance to its own physical DLL with a different name. Each loaded with Native.loadLibrary(). (it might only work if for the same Library interface, multiple DLL can be loaded)

• Do I need to load the DLL in different JVMs for parallelism.

Does anyone know whether one of these thoughts might work / or why it can't work. Other suggestions? Thanks, Martin

Answer 1

On Windows, you can't load the same DLL twice into one process. I say your best option for achieving parallelism is to have several processes executing concurrently, instead of one process.