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This article introduces the relevant knowledge of "how to count the threads of a process in Linux". In the operation of actual cases, many people will encounter such a dilemma, so 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!

Problem: I am running a program that spawns multiple threads at run time. I want to know how many threads the program will have when it runs. What is the easiest way to check the number of threads in a process in Linux?

If you want to see the number of threads per process in Linux, there are two ways to do this.

Method 1: / proc

The proc pseudo-file system, which resides in the / proc directory, is the easiest way to see the number of threads in any active process. The / proc directory is output as a readable text file, providing information about existing processes and system hardware, such as CPU, interrupts, memory, disks, and so on.

$cat / proc//status

The above command displays details of the process, including the process status (for example, sleeping, running), the parent process PID,UID,GID, the number of file descriptors used, and the number of context switches. The output also includes the number of buses created by the process as shown below.

Threads:

For example, check the number of threads in the PID 20571 process:

$cat / proc/20571/status

The output shows that the process has 28 threads.

Alternatively, you can simply count the number of subdirectories in / proc//task, as shown below.

$ls / proc//task | wc

This is because, for each thread created in a process, a corresponding directory is created in / proc//task, named its thread ID. Thus the total number of directories in / proc//task represents the number of threads in the process.

Method 2: ps

If you are a loyal user of the powerful ps command, this command can also tell you the number of threads of a process (with the "H" option). The following command will output the number of threads in the process. The "h" option needs to be placed first.

$ps hH p | wc-l "how to count the threads of a process in Linux" ends here. Thank you for 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!

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