Shulou(Shulou.com)06/02 Report--

This article introduces the knowledge of "what is the relationship and difference between threads and processes". In the operation of actual cases, many people will encounter such a dilemma. Next, let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

Relationship: a thread is the basic execution unit of a process, and all tasks of a process are executed in a thread; if a process wants to execute a task, it must have a thread. Differences: 1, threads of the same process share the address space of the process, while processes are independent address space; 2, threads within the same process share the resources of the process, while resources between processes are independent.

The operating environment of this tutorial: windows10 system, Dell G3 computer.

The relationship between threads and processes

Thread definition

A thread is the basic execution unit of a process, and all tasks of a process are executed in the thread.

If a process wants to perform a task, it must have a thread, and the process must have at least one thread

By default, the program starts a thread, which is called the main thread or UI thread

Process definition

A process is an application that is running on the system

Each process is independent, and each process runs in its dedicated and protected memory

The difference between process and thread

Address space: threads of the same process share the address space of this process, while processes are independent address space.

Resource ownership: threads within the same process share the resources of their own process (such as memory, cpu, etc.), but the resources between processes are independent.

After a process crashes, it does not affect other processes in protected mode, but a thread crashes and the whole process dies. So multi-processes are more robust than multi-threads.

When the process is switched, it consumes a lot of resources and has high efficiency. So when it comes to frequent switching, using threads is better than processes. Similarly, if concurrent operations are required to be carried out at the same time and some variables are shared, you can only use threads and not processes.

Execution process: each independent process has an entry for program execution, a sequential execution sequence, and a program entry. However, threads cannot execute independently and must be stored in the application, which provides multiple thread execution control.

Threads are the basic unit of processor scheduling, but processes are not.

Extended data: the meaning of multithreading

Advantages

It can appropriately improve the execution efficiency of the program.

Can appropriately improve the utilization of resources (CPU, memory)

After the execution of the task on the thread is completed, the thread will automatically destroy

Shortcoming

Starting threads takes up a certain amount of memory space (by default, each thread takes up 512 KB)

If you open a large number of threads, it will occupy a lot of memory space and reduce the performance of the program.

The more threads there are, the more overhead CPU will have on the calling thread

Programming is more complex, such as communication between threads and multi-thread data sharing

This is the end of the content of "what is the relationship and difference between threads and processes". Thank you for your reading. If you want to know more about the industry, you can follow the website, the editor will output more high-quality practical articles for you!

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.