[Oracle] ORA-00845 : MEMORY TARGET not supported on this system

I used Oracle 11g in CentOS VM image. this image is allocated 16GB memory. But after reducing memory to 8GB, oracle instance was not started.



This error comes up because you tried to use the Automatic Memory Management (AMM) feature of Oracle 11g R2. It seems that your shared memory filesystem (shmfs) is not big enough. In this case, you should increase shmfs.

1. Check shared memory filesystem size

# df -h

2. Remount and increase size

# umount tmpfs
# mount -t tmpfs shmfs -o size=8192m /dev/shm

3. Startup database instance

4. Check parameter related with memory