Solution
Investigate the following approaches for reducing your LabVIEW EXE and PPL build times:
Increased (Single) Processor Speed
LabVIEW EXE and PPL builds are single-threaded. This means that no matter how many cores your machine has, only one of them will be used for the build. As a result, the processor speed (i.e. the "GHz") is the most important hardware-related factor in building LabVIEW code. Put your code on a machine with more GHz, and in most cases your builds will be faster.
Remove Circular Dependencies
Circular dependencies occur when VIs that belong to a LabVIEW library or class call VIs in another library or class, and vice-versa. For example, a VI in First.lvclass calls a VI in Second.lvclass, a VI in Second.lvclass calls a VI in First.lvclass, and these classes don't inherit from one another. The more circular dependencies you have between libraries, the longer it will take for your code to build.
Break apart the monolithic EXE
If your application consists of a monolithic executable, consider refactoring your code into a plugin-based system where the executable is relatively light, and it pulls in dependencies from separately-built and maintained libraries. When the software is designed with this modularity, changes to the code are done to isolated libraries, whose resulting individual build times are a fraction of the build time of the monolithic application. In the case of re-building code changes, it's usually one or two of these components that need to be built, not the entire application.
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