2.8 Increasing the Number of Active Cores on Database Servers

You can increase the number of active cores on Oracle Exadata using capacity-on-demand.

The number of active cores on the database servers on Oracle Exadata Database Machine X4-2 and newer systems can be reduced during installation. The number of active cores can be increased when additional capacity is needed. This is known as capacity-on-demand.

Additional cores are increased in increments of 2 cores on 2-socket systems, and in increments of 8 cores on 8-socket systems. The following table lists the capacity-on-demand core processor configurations.

Table 2-3 Capacity-on-Demand Core Processor Configurations

Oracle Exadata	Eligible Systems	Minimum Cores per Server	Maximum Cores per Server	Core Increments
Oracle Exadata X10M	Any configuration except Eighth Rack	14	192	From 14 to 192, in increments of 2: 14, 16, 18, …, 190, 192
Oracle Exadata X9M-2	Any configuration except Eighth Rack	14	64	From 14 to 64, in increments of 2: 14, 16, 18, …, 62, 64
Oracle Exadata X9M-2	Eighth rack	8	32	From 8 to 32, in increments of 2: 8, 10, 12, …, 30, 32
Oracle Exadata X7-2, X8-2, and X8M-2	Any configuration except Eighth Rack	14	48	From 14 to 48, in increments of 2: 14, 16, 18, …, 46, 48
Oracle Exadata X7-2, X8-2, and X8M-2	Eighth rack	8	24	From 8 to 24, in increments of 2: 8, 10, 12, …, 22, 24
Oracle Exadata Database Machine X6-2	Any configuration except Eighth Rack	14	44	From 14 to 44, in increments of 2: 14, 16, 18, …, 42, 44
Oracle Exadata Database Machine X6-2	Eighth rack	8	22	From 8 to 22, in increments of 2: 8, 10, 12, …, 20, 22
Oracle Exadata Database Machine X5-2	Any configuration except Eighth Rack	14	36	From 14 to 36, in increments of 2: 14, 16, 18, …, 34, 36
Oracle Exadata Database Machine X5-2	Eighth rack	8	18	From 8 to 18, in increments of 2: 8, 10, 12, 14, 16, 18
Oracle Exadata Database Machine X4-2	Full rack Half rack Quarter rack	12	24	From 12 to 24, in increments of 2: 12, 14, 16, 18, 20, 22, 24
Oracle Exadata X7-8, X8-8, X8M-8, and X9M-8	Any configuration	56	192	From 56 to 192, in increments of 8: 56, 64, 72, …, 184, 192
Oracle Exadata X6-8 and X5-8	Any configuration	56	144	From 56 to 144, in increments of 8: 56, 64, 72, …, 136, 144
Oracle Exadata Database Machine X4-8	Full rack	48	120	From 48 to 120, in increments of 8: 48, 56, 64, …, 112, 120

Note:

Oracle recommends licensing the same number of cores on each server, in case of failover.

Database servers can be added one at a time, and capacity-on-demand can be applied to the individual database servers. This option includes Oracle Exadata Database Machine X5-2 Eighth Racks.

The database server must be restarted after enabling additional cores. If the database servers are part of a cluster, then they can be enabled in a rolling fashion.

1. Verify the number of active physical cores using the following command:

   DBMCLI> LIST DBSERVER attributes coreCount
   

2. Use the following command to increase the number of active physical cores:

   DBMCLI> ALTER DBSERVER pendingCoreCount = new_number_of_active_physical_cores
   

3. Verify the pending number of active physical cores using the following command:

   DBMCLI> LIST DBSERVER attributes pendingCoreCount
   

4. Restart the server (if required).

   You must restart the server to enable the new active cores if the output from the previous ALTER DBSERVER command states that a reboot is required or if the command provides no output about restarting the server.

   A server reboot is not required only if that is indicated in the output from the previous ALTER DBSERVER command.

5. Verify the number of active physical cores using the following command:

   DBMCLI> LIST DBSERVER attributes coreCount