Simon Krenger

For my own reference, as I was asked what the minimum memory size for an Oracle database is. It turns out, that both in Oracle 11g R2 (11.2) as well as in Oracle 12c (12.1), the minimum value for MEMORY_TARGET (sum of SGA and PGA) is 152MB:

There is always something that gets in the way. One problem I regularly stumble upon when installing a new Oracle 11g R2 installation is the following error when I try to start the database:

SQL> startup nomount;
ORA-00845: MEMORY_TARGET not supported on this system

So I keep this post mainly for my own reference when installing a new database on a Linux system.

This error comes up because you tried to use the Automatic Memory Management (AMM) feature of Oracle 11g R2. Well done, but it seems that your shared memory filesystem (shmfs) is not big enough. So let’s look at the steps necessary to enlarge your shared memory filesystem to avoid the error above.