16.20 - Setting Semaphore Parameters - Teradata Tools and Utilities

Teradata® Tools and Utilities for Linux Installation Guide Amazon Linux 2, CentOS, OEL, RedHat, SLES, Ubuntu

Teradata Tools and Utilities
Release Number
Release Date
November 2020
Content Type
Publication ID
English (United States)
The Teradata Parallel Transporter Base installation checks the values of the semaphore parameters for the required minimum values. The installation does not support a formula value for a kernel parameter. If the value for a kernel parameter is less than the required minimum value, the installation recommends increasing the value to the minimum value.

The most significant parameter is the semmns semaphore parameter, which determines the number of semaphores in the entire system.

The default configuration allows 1000 semaphores in concurrent use. The default semmni parameter value is 1000. The default semmns parameter value is 1000.

  1. Log on as the root user.
  2. Check the value of the semmns semaphore parameter:
    /sbin/sysctl kernel.semmns
  3. Add the following line in the /etc/rc.d/rc.local file to increase the semmns parameter value to 1000:
    echo 1000 > /proc/sys/kernel/semmns
  4. To shut down the system in one minute, type:
    /sbin/shutdown -r +1