Database startup reports ORA-27154 ORA-27300 ORA-27301 ORA-27302 Error

Database startup reports ORA-27154 ORA-27300 ORA-27301 ORA-27302 Error

Today, my colleague encountered an Oracle startup problem,
 
SQL> startup
 
ORA-27154: post/wait create failed.
 
ORA-27300: OS system dependentoperation: semget failed with status: 28
 
ORA-27301: OS failure message: No spaceleft on device
 
ORA-27302: failure occurred at: sskgpsemsper

 

[Oracle @ info bin] $ df-h
 
Filesystem Size Used Avail Use % Mounted
 
/Dev/sda2 764 GB 572G 154G 79%/
 
/Dev/sda5 57G 3.5G 51G 7%/home
 
/Dev/sda3 473G 309G 140G 69%/u01
 
/Dev/sda1 190 M 25 M 156 M 14%/boot
 
Tmpfs 32G 16G 16G 52%/dev/shm
 
Checking the disk does not seem to be a problem with the disk space.
 
This problem exists in Versions later than 11.2.0.1 because the semmns value is too low. This value is configured in/etc/sysctl. conf.
 

Kernel. sem = semmsl semmns semopm semmni
 
Original Value:
 
Kernel. sem = 250 32000 100 128
 
Change the value:
 
Kernel. sem = 256 32768 100 228
 
Save and exit after modification. Then run sysctl-p to make the modified parameters take effect, and then restart the database. OK.
 
The semaphores parameter optimization principles are as follows:
 
1. Calculate the minimum total semaphorerequirements using the following formula:
 
2 * sum (process parameters of all databaseinstances on the system) + overhead for background processes + system and otherapplications.
 
2. Set semmns (total semaphores systemwide) to this total.
 
3. Set semmsl (semaphores for each set) to256
 
4. Set semmni (total semaphores sets) tosemmns devided by semmsl, rounded up to the nearest multiple of 1024