kernel.sem = 500 32000 100 256 # SEMMSL, SEMMNS, SEMOPM, SEMMNI Apply: sysctl -p Edit /etc/security/limits.conf :
ipcs -ls showed SEMMNI=128 . The database’s PROCESSES=1500 . Each Oracle process consumes a semaphore. With multiple instances, 128 semaphore sets were insufficient. Ora-27103 Internal Error Svr4 Error 11 Resource Temporarily
ALTER SYSTEM SET processes=800 SCOPE=SPFILE; Then restart. Check MyOracleSupport for known bugs matching your version (e.g., Bug 9854529 for Solaris 10). Case Study: A Real-World Example Symptom: After increasing the SGA from 8GB to 16GB, the database failed to start with ORA-27103. kernel
cat /proc/sys/kernel/sem # Output: 250 32000 100 128 # Fields: SEMMSL, SEMMNS, SEMOPM, SEMMNI Increase SEMMNI or SEMMSL via sysctl if needed. Switch to the Oracle user and run: Case Study: A Real-World Example Symptom: After increasing
oracle soft nproc 65536 oracle hard nproc 65536 Reboot or re-login as oracle. If the instance is misconfigured: