static

There are a lot of issues with the singleton pattern. I'm aware of that. But the singleton pattern is an ideal use case for a variable, which can only be initialized in a thread-safe way. From that point on, you can use it without synchronization. So in this post, I discuss different ways to initialize a singleton in a multithreading environment. You get the performance numbers and can reason about your use cases for the thread-safe initialization of a variable.

The story is simple if the data is not modified when shared between threads. The data has only to be initialized in the thread-safe way. It is not necessary to use an expensive lock for each access.