How much maximum RAM is used by Oracle XE ?

User_C3D23

Hi,

We are running Oracle XE on a server with 48 GB RAM out of which only 24GB is usable. I read that Oracle XE uses 2GB RAM even if more is available. This means we do not get performance increase from our server right?

L. Fernigrini

XE is the free version of Oracle and has a limit to use 2Gb of RAM and 12 Gb of storage (although you can store more data than previous XE versions since you can enable compression). It also uses only 2 CPU cores:

https://blogs.oracle.com/database/post/oracle-database-21c-xe-generally-available

If you need to use more RAM or Storage or CPUs in a production environment, then XE is not the edition for you,

L. Fernigrini

XE is the free version of Oracle and has a limit to use 2Gb of RAM and 12 Gb of storage (although you can store more data than previous XE versions since you can enable compression). It also uses only 2 CPU cores:

https://blogs.oracle.com/database/post/oracle-database-21c-xe-generally-available

If you need to use more RAM or Storage or CPUs in a production environment, then XE is not the edition for you,

EdStevens

In addition to spot-on comment by @L. Fernigrini , your question assumes that more memory means better performance. But if your performance bottleneck is something other than a lack of available memory, then throwing a whole terrabyte of memory at it will not improve performance one whit.

User_C3D23

Thank you for both answers. It confirmed my understanding. I am transforming flat file data into rdbms, for example I am running procedure on a temp table with about 1 million records to convert dates, find certain data from other tables and inserting into actual table. This takes lot's of time even though I do it in chunks. The procedure is able to process about a thousand records per second but slows down later. That's why I wanted to know that in case of Oracle xe, increasing RAM will not be useful.

EdStevens

You should approach this just like any other performance tuning issue. Instead of jumping to some silver-bullet conclusion about what might resolve the issue, perform some actual performance analysis and see exactly where the bottleneck is. If you need help on how to perform that analysis, there is a whole forum space, here, dedicated to performance issues.

cormaco

The procedure is able to process about a thousand records per second but slows down later.

That procedure might be very inefficently written.

EdStevens

That procedure might be very inefficently written.

Indeed.

I always refer back to a section in the Oracle7 Server Tuning, Release 7.3.3. Yes, 7.3. And it still applies.

Prioritized Steps of the Tuning Method

The recommended method for tuning an Oracle database prioritizes steps in order of diminishing returns: steps which have the greatest impact on performance are listed first. For optimal results, therefore, tackle tuning issues in the order listed: from the design and development phases through instance tuning.

Step 1: Tune the Business Rules

Step 2: Tune the Data Design

Step 3: Tune the Application Design

Step 4: Tune the Logical Structure of the Database

Step 5: Tune the SQL

Step 6: Tune the Access Paths

Step 7: Tune Memory Allocation

Step 8: Tune I/O and Physical Structure

Step 9: Tune Resource Contention

Step 10: Tune the Underlying Platform(s)

'Worrying about server memory comes under step 10 -- the very last/least priority.