Shulou(Shulou.com)06/03 Report--

This article mainly explains "what is the meaning of Java green thread". The content of the article is simple and clear, and it is easy to learn and understand. Please follow the editor's train of thought to study and learn what Java green thread means.

What on earth is the Java green thread? These problems require us to look at the essence of the problem. Let's take a look at Java green threads (Green Thread) as opposed to operating system threads (Native Thread).

Operating system thread (Native Thread) means that the thread in the program is actually mapped to the thread of the operating system, and the running and scheduling of the thread is controlled by the operating system.

Java green thread (Green Thread) means that the threads in the program are not really mapped to the threads of the operating system, but are scheduled by the language runtime platform itself.

Threads in the current version of the Python language can be mapped to operating system threads. The threads of the current version of the Ruby language are green threads and cannot be mapped to the threads of the operating system, so the threads of the Ruby language run slowly.

Is Java green thread slower than operating system thread? Of course not. In fact, the opposite may be true. Ruby is a special example. The thread scheduler is not very mature.

At present, the popular implementation model of threads is Java green threads. Stackless Python, for example, introduces a lighter concept of green threads. In terms of thread concurrent programming, it is better than Python in terms of running speed and concurrent load.

Another more famous example is ErLang, an open source language developed by Ericsson.

ErLang's Java green thread concept is very thorough. The thread of ErLang is not called Thread, but Process. This can easily be confused with the process. We should pay attention to the distinction here.

There is no need for synchronization between ErLang Process. Because all variables in the ErLang language are final, no change in the value of the variable is allowed. So synchronization is not needed at all.

Another advantage of final variables is that there can be no cross-references between objects, it is impossible to form a circular association, and the associations between objects are unidirectional and tree-like. Therefore, the algorithm of memory garbage collection is also very efficient. This enables ErLang to achieve the Soft Real Time (soft real-time) effect. This is not an easy task for a language that supports memory garbage collection.

Thank you for your reading, the above is the content of "what is the meaning of Java green thread", after the study of this article, I believe you have a deeper understanding of what the meaning of Java green thread is, and the specific use needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.