What are the possible effects of setting the pid.max value too high or too low ?

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux 6.4

Issue

  • Are there any kernel parameters that are set automatically based on the value of pid.max ?
  • What are the possible effects of setting the pid.max value too high or too low ?
  • All about pid.max value.

Resolution

  • Changing the value of pid_max does not affect the settings of any other kernel parameters.
  • If this value is set to very low and if pid_max is reached the counter, it simply wraps back to the beginning. User's will not be able to create new processes once the value is reached. After reaching the limit, user's will get an error message that no more process can be created.

  • Setting the high values does not have any effect a pid's regardless of how many processes are actually there. This is to prevent from burning (unswappable) kernel memory. If there is really that many processes running at once, then system will be using that memory regardless of whether it was sparsely allocated.

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