Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Performance Tuning Guide

Semaphores and Shared Memory

Add (or edit) the following lines in the /etc/system file:

set shmsys:shminfo_shmmax=0xffffffff
set shmsys:shminfo_shmseg=128
set semsys:seminfo_semmnu=1024
set semsys:seminfo_semmap=128
set semsys:seminfo_semmni=400
set semsys:seminfo_semmns=1024

These settings affect the number of semaphores and the shared memory. These are more relevant for the machine on which HADB server is running than for Application Server.