You are receiving this error either because your kernel parameters are not set correctly, or the SGA of the database the DBCA is attempting to create is too large to fit into the available physical memory segments.
First, check that the kernel parameters are as follows:
SHMMAX = 2147483648 SHMMIN = 1 SHMMNI = 100 SEMMNS = 1000 SEMMSL = 250 SEMMNI = 100 SEMOPM = 100
Refer to the installation guide on Oracle's Technology Network Web site for an explanation of each of these parameters.
If the parameters have been set correctly, lower the memory requirements for the database being created. This will create a smaller SGA which may allow the database creation to complete successfully.
This was first published in March 2006