5.2.3.9 Controlling Access to PMEM Cache and PMEM Log

Note:

This topic applies only to Oracle Exadata System Software releases before 23.1.0. Otherwise, see Controlling Access to XRMEM Resources.

You can use IORM to manage access to persistent memory (PMEM) cache and PMEM log.

You can use the pmemcache and pmemlog attributes in the interdatabase plan to control access to PMEM cache and PMEM log. When set in the interdatabase plan, these attributes control access by a specific database.

The following example shows how to disable PMEM cache and PMEM log for the prod_test and prod_dev databases. In the example, PMEM log is also disabled for the dw_test database.

CellCLI> ALTER IORMPLAN                                        -
         dbplan=((name=prod, pmemcache=on, pmemlog=on),        -
                (name=dw, pmemcache=on, pmemlog=on),           -
                (name=prod_test, pmemcache=off, pmemlog=off),  -
                (name=prod_dev, pmemcache=off, pmemlog=off),   -
                (name=dw_test, pmemcache=on, pmemlog=off))

You can also use these attributes in conjunction with other attributes. For example:

CellCLI> ALTER IORMPLAN                                                 -
         dbplan=((name=prod, share=8, pmemcache=on, pmemlog=on),        -
                (name=dw, share=6, pmemcache=on, pmemlog=on),           -
                (name=prod_test, share=2, pmemcache=off, pmemlog=off),  -
                (name=prod_dev, share=1, pmemcache=off, pmemlog=off),   -
                (name=dw_test, share=2, pmemcache=on, pmemlog=off),     -
                (name=other, share=1))

You do not need to explicitly set pmemcache=on or pmemlog=on because they are the default settings.