Author: Zen and the Art of Computer Programming
1. Background introduction
For any programming language, memory management and garbage collection are basic functions. Before the GC mechanism, programmers needed to manually allocate and release memory to achieve the purpose of dynamically allocating and releasing resources. When problems such as memory leaks and stack overflows occur in the code, you need to find the leak points of these memories. After using the GC mechanism, all this can be processed automatically.
For the Go language, GC (Garbage Collection) is the garbage collection mechanism and an automatic memory management mechanism implemented by the compiler. The current Go language has become the main cloud computing language. Due to its efficient garbage collection mechanism, Go language has become one of the most popular static languages. As the community continues to grow and technology is updated and iterated, the Go language continues to attract more and more people's attention.
In this series of tutorials, I will take you on the theme of Go language memory management and garbage collection to take you to find out. As an open source, rapid development, statically typed, and safe programming language, Go language can help us simplify programming work, improve code quality, and execute programs faster. Therefore, mastering Go language memory management and garbage collection skills is of great significance to improving our work efficiency and solving practical problems.
2. Core concepts and connections
2.1 GC process
In the Go language, the GC process is mainly divided into three stages: mark clearing, reference counting and three-color mark clearing method.
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Phase 1: Mark-Sweep
This phase occurs during the marking phase. In the initial state, all objects are white. If you start from the root object and traverse all reachable objects and mark them as gray; then traverse the entire heap and clear the unmarked gray objects. -
Phase 2: Reference Counting
This phase occurs after the marking phase. Go language uses reference counting method to track and recycle garbage objects. Its basic idea is to track the number of references of each object.