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ORA-27102 Database Will Not Start With SHMMAX Set To 8589934592 (8GB) (Doc ID 461519.1)

Last updated on JULY 27, 2023

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 10.1 to 10.2]
Red Hat Advanced Server
Linux x86
Linux x86-64
Linux x86-64Linux x86Red Hat Advanced Server


When shmmax is set to 8589934592 (which is half the size of RAM ), Database startup fails with error ORA-27102. This is no matter what the init.ora settings are (whether sga_max_size, sga_target etc.. are set or not)

If shmmax is set to any other value (even 8000000000, or 4294967295, or 12000000000, or 16000000000, ...) the database starts OK.

SQL> startup nomount
ORA-27102: out of memory
Linux Error: 22: Invalid argument



SHMMAX set to 8589934592 (8GB) with 16GB RAM


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