During installation, the Teradata Parallel Transporter Base package checks for the system kernel values and increases them if necessary.
| Parameter | Maximum Value | Description |
|---|---|---|
| semmni | 1000 | Maximum number of semaphore sets in entire system |
| semmns | 1000 | Maximum number of semaphores in entire system |
| semmnu | 2500 | Maximum number of processes that can have undo operations pending on semaphores |
| semmap | 1000 | semmap value |
The Teradata Parallel Transporter Base installation does not support formula value. If the kernel value is a formula, then the Teradata Parallel Transporter Base installation displays a warning message.
The most significant value is the semmns semaphore parameter, which determines the number of semaphores in the entire system. The default configuration allows 1000 semaphores in concurrent use.
If any of the semaphore parameters is less than the minimum value, the Teradata Parallel Transporter Base installation recommends increasing the semaphore parameter to the minimum value using the kmtune command. This requires a root login. Use the following procedure to increase the semaphore parameter to the minimum value.
- To increase the semmap parameter to 1000: /usr/sbin/kmtune -s semmap=1000
- After the semaphore parameters are changed, rebuild the kernel using the mk_kernel command as the root user: /usr/sbin/mk_kernel
- After rebuilding the kernel, save the current vmunix file: cp /stand/vmunix /stand/vmunix.prev
- Move the new vmunix file into the /stand directory: mv /stand/build/vmunix_test /stand/vmunix
-
Move the new vmunix file into the /stand directory:
/usr/sbin/reboot
If there is a change to the kernel value, the following kernel parameters require a kernel rebuild and reboot: semmap, semmni, semmns and semmnu.