I had to move part of the Code to C for different reason (imaging device) and used that code in a .net application. But allocating unmanaged memory on .nets heap led to memory fragmentation and while overall there was enough memory available, you ran into allocation errors since unmanaged memory needed to be allocated in one successive block. Usually doesn't happen, but if you have large objects like high resolution images in memory, you can quickly run into problems. And to my knowledge there was no way to check if there was enough successive memory available.

Had to wait on a patch for .net... not a problem anymore today, although I don't know the details how they solved the problem.