In modern programming languages, memory management is a crucial issue. The purpose of memory management is to control memory usage while the application is running. If an application requests too much memory, it can cause performance degradation or eventually even crash.
Golang is an efficient programming language. Its built-in automatic garbage collection mechanism provides programmers with great convenience and convenience. This mechanism allows Golang programmers to focus on writing code rather than caring about memory management.
Golang that fits the context, the mark-and-clear algorithm based on generational division, or the Tricolor algorithm, is a so-called "stop-copy"-based GC algorithm, and it is also the garbage currently used in the Go language recycling algorithm. This algorithm allows for multi-cycle garbage collection, which provides good control over memory usage while the program is running.
In the Tricolor algorithm, recursive traversal is performed through stack frames, which can be interrupted and resumed at any time, making it easy to control and arrange during concurrent garbage collection. It's intuitive, easy to understand, and runs very efficiently.
Golang’s GC algorithm mainly includes the following two stages:
1. Marking stage (Marking)
In the marking stage, the garbage collector will traverse the entire heap, and Mark the objects in . The purpose of the marking phase is to identify garbage objects that should be cleaned and recycled. During the traversal, as long as the program reaches the location referenced by any object, the object will be marked as "alive".
2. Clearing phase (Clearing)
In the clearing phase, the garbage collector will release all unmarked garbage objects. This frees up memory space for objects that do not have any references.
In Golang, the garbage collector is performed in units of "single time slices". When the garbage collector executes, all other threads of the application are suspended. After garbage collection is complete, all suspended threads are resumed.
Although it is a very efficient GC algorithm, the biggest problem of the Tricolor algorithm is that it increases the delay time of the program, mainly because the time of marking and clearing takes up the execution time of the program.
In order to avoid this delay problem, Golang introduced STW (Stop The World) technology, that is to say, when the garbage collector starts operating, all concurrently executing threads will be suspended until the garbage collection The processor execution is completed.
In addition, since Golang allocates all variables in memory, there is no need to use memory allocation functions such as malloc or free. This makes Golang programs very efficient and avoids common memory leak problems.
In short, Golang’s GC algorithm is very excellent. It provides programmers with convenience and convenience and avoids some common memory management errors. Although it may increase some latency problems, these latency problems can be solved by using STW technology, and Golang can still perform well in terms of program running efficiency.
The above is the detailed content of golang mark clear. For more information, please follow other related articles on the PHP Chinese website!