Can RAM used by Oracle be freed on the fly?


I have an AIX LPAR with Live Partition Mobility, and when I move this LPAR from one box to another, I would like to be able to free the RAM used by Oracle on the fly, is this possible?

For example, if I have the LPAR with 64GB RAM on use and I move it over a box with 48GB RAM, can I tell Oracle to drop some schemas or tables from RAM to be able to move over to the 48GB machine???

I know it can be done with a stop/start of Oracle DB via editing Oracle's config files, but it would be fantastic to automate it fully and on the fly.

Thanks in advance.
LVL 10
Carlos IjalbaSenior SysadminAsked:
Who is Participating?
slightwv (䄆 Netminder) Commented:
Oracle can use up to memory_max_target.  That cannot be changed on the fly.

Modifiable No
If you are using the automatic memory management, as slihtwv says, you cannot modify MEMORY_MAX_TARGET, but you can reduce MEMORY_TARGET on the fly.
Carlos IjalbaSenior SysadminAuthor Commented:
Thanks guys,

So, If I start up an instance without MEMORY_MAX_TARGET, but set a MEMORY_TARGET of say 60GB, can I afterwards setup a MEMORY_TARGET of 48GB and Oracle will adjust accordingly??

Or MEMORY_TARGET is just to increase RAM, but not to decrease it???
slightwv (䄆 Netminder) Commented:
Sorry but no.

The online docs typically has everything you need:

In a text-based initialization parameter file, if you omit MEMORY_MAX_TARGET and include a value for MEMORY_TARGET, then the database automatically sets MEMORY_MAX_TARGET to the value of MEMORY_TARGET. If you omit the line for MEMORY_TARGET and include a value for MEMORY_MAX_TARGET, the MEMORY_TARGET parameter defaults to zero. After startup, you can then dynamically change MEMORY_TARGET to a nonzero value, provided that it does not exceed the value of MEMORY_MAX_TARGET.
Carlos IjalbaSenior SysadminAuthor Commented:
Thanks for your responses.
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.