Home/ Questions/Q 7799365
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-02T00:17:08+00:00

This is a sequel to my previous question . I am using fork to

  • 0

This is a sequel to my previous question. I am using fork to create child process. Inside child, I am giving command to run a process as follows:

if((childpid=fork())==0)
{
system("./runBinary ");
exit(1)
}

My runBinary has the functionality of measuring how much time it takes from start to finish.

What amazes me is that when I run runBinary directly on command-line, it takes ~60 seconds. However, when I run it as a child process, it takes more, like ~75 or more. Is there something which I can do or am currently doing wrong, which is leading to this?

Thanks for the help in advance.
MORE DETAILS: I am running on linux RHEL server, with 24 cores. I am measuring CPU time. At a time, I only fork 8 child (sequentially), each of which is bound to different core, using taskset (not shown in code). The system is not loaded except for my own program.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    The system() function is to invoke the shell. You can do anything inside it, including running a script. This gives you a lot of flexibility, but it comes with a price: you’re loading a shell, and then runBinary inside it. Although I don’t think loading the shell would be responsible to so much time difference (15 seconds is a lot, after all), since it doesn’t seem you need that – just to run the app – try using something from the exec() family instead.

    • 0