Using more available RAM 1

[sfunk]

Hello,

Pardon this simplistic request.

Windows2000 Server / Oracle 8i

I have a server that has nearly 2GB of available RAM. Right now Oracle is only using about 512MB. Is there a simple way to allocate more RAM to Oracle? I understand there are a million ways to improve performance that is very specific to the specific situation. However, Since there is an abundance of available RAM I was hoping that I could allocate more RAM to Oracle in general or the instance that will give me some performance increase in itself.

Thank you for any suggestions.
Steve

 

[karluk]

As far as I know, Oracle still recommends allocating about 1/3 to 1/2 of available memory to your SGA and leaving the rest available for other processes. That means you can increase your SGA somewhat and still be within these guidelines. I would suggest adding another 100 Mb and see how things go. You can make additional adjustments later if you see significant performance benefit.

Then you have to decide where to allocate the extra memory. The following startup parameters affect SGA size.

db_block_buffers
shared_pool_size
large_pool_size
java_pool_size
log_buffers

To do a really good job of allocating space, you would have to collect performance statistics and analyze where bottlenecks are occurring. In the absence of performance statistics, I would be tempted to add all the extra memory to the database buffers. The parameter to do this is db_block_buffers. You would make the following calculation, which requires you to know your database block size

new db_block_buffers = old db_block_buffers + 1048576/db_block_size

Shutdown your database, change the db_block_buffers parameter, and restart the database.

 

[karluk]

Oops, that calculation only allocates an extra 1 Mb to database buffers. For 100 Mb the calcation is

new db_block_buffers = old db_block_buffers + 104857600/db_block_size

 

[sfunk]

Great, Thank you.

I appreciate the time you took to give me an answer right on target.

Sincerely,
steve