Using the Strace Debugging tool

Strace is a software debugging tool in a Linux environment that monitors the system calls used by an application and the system information it receives.

Strace is a useful gadget that allows you to know what a program does in the background by tracking the system. Strace is a basic debugging tool that is installed by default on most Linux systems, but even if you're not tracking a problem, it's an excellent software. It tells you a lot of information about how a Linux program works.

Let's start with a simple UNIX command pwd, and then delve deeper into what the command does in the process of accomplishing its tasks. Start Xterm to create a controlled environment for experimentation, and then enter the following command:

$ pwd

This PWD command displays the current working directory. On my computer, the output at that time was:

/home/bill/

Such a simple function hides the complexity of the underlying command (all computer programs are, by the way). To really understand its complexity, run the PWD command again using the Strace tool:

$ strace pwd

With this command, you can see that UNIX computers perform quite a lot of operations while displaying and enumerating the current working directory.

Original: http://www.oschina.net/question/12_7536

Reference to this article: http://blog.s135.com/file_get_contents/2/1/

PHP-CGI Process CPU 100% and the relationship between the file_get_contents function needs to find one of the CPU 100% of the php-cgi process PID, with the command to track, then you can determine is file_get_contents () caused of the problem.