I'm trying to move some computations to Azure cloud services. One of the steps of the workflow I'm trying to implement includes running a Win32 desktop application generating a file. Obviously, we cannot have a user interaction for cloud calculations, so the application is launched with command line arguments. The process starts, generates a file, and then exists. At the moment I cannot refactor the code and move this functionality to command-line windowless utility.
First, I chose Azure Functions because they are intended for event-driven short calculations, and that's exactly what I need. Also they are cheap. But I encountered a problem that processes in Azure Functions are being executed inside a sandbox blocking User32/GDI32 system calls and thus preventing me from launching desktop applications.
Another solution I came up with is mounting a virtual machine drive with all needed Visual C++ redistributables installed and then using Azure Batch with nodes based on the pre-configured drive. But this solution has another drawbacks, since it takes minutes to mount a new node. Of course, I could have some nodes that are always active, but anyway the further scaling is slow and having active nodes is not so cheap. Also I have a feeling that Azure Batch is a bit overkill, because there is no need for HPC in my case. Azure Functions' computation capabilities are enough for me.
Is there some kind of compromise solution? So that I would have a solution with fast scaling and quick responses, but with no need to establish Azure Batch based on Azure Virtual Machines?