Starting with the Oracle Exadata X11M system family and Oracle Exadata System Software release 25.1.0, you can reduce database server power consumption by using a low power mode during low-demand periods.

Using this capability, you can define a schedule to automatically switch the server into a low power mode during predictable low-demand periods, such as overnight or on weekends. At any point, you can manually switch the low power mode on or off. At all times, the system monitors demand and automatically switches off the low power mode to protect system performance if required.

To specify a low power mode schedule on a database server, you can set the lowPowerModeSchedule attribute. The lowPowerModeSchedule attribute value contains one or more entries that define the start time, duration in minutes (up to 1440), and frequency (daily or weekly) of each scheduled low power mode period.

For example, the following command creates a low power mode schedule with three entries:

• The first entry schedules low power mode to run from 6 pm to 6 am the next day on every day starting from January 3, 2025.

• The second entry schedules low power mode to run from 6 am to 6 pm every Saturday starting from January 4, 2025.

• The third entry schedules low power mode to run from 6 am to 6 pm every Sunday starting from January 5, 2025.

DBMCLI> ALTER DBSERVER lowPowerModeSchedule=((startTimestamp="2025-01-03T18:00:00-07:00",durationMinutes=1440,frequency=daily),
                                             (startTimestamp="2025-01-04T06:00:00-07:00",durationMinutes=1440,frequency=weekly),
                                             (startTimestamp="2025-01-05T06:00:00-07:00",durationMinutes=1440,frequency=weekly))

In the previous example, the low power mode schedule is completely overwritten by the specified entries. You can also modify an existing schedule. To add to an existing schedule, you can use the += operator. For example:

DBMCLI> ALTER DBSERVER lowPowerModeSchedule+=((startTimestamp="2024-01-06T06:00:00-07:00",durationMinutes=120,frequency=weekly))

Likewise, you can remove specific entries from an existing schedule by using the -= operator. For example:

DBMCLI> ALTER DBSERVER lowPowerModeSchedule-=((startTimestamp="2025-01-03T18:00:00-07:00",durationMinutes=1440,frequency=daily))

To remove all entries in the low power mode schedule, specify lowPowerModeSchedule=NULL. For example:

DBMCLI> ALTER DBSERVER lowPowerModeSchedule=NULL

At any point, you can view the current low power mode schedule by listing the lowPowerModeSchedule attribute value. For example:

DBMCLI> LIST DBSERVER attributes lowPowerModeSchedule

In addition to specifying a low power mode schedule, you can manually regulate the low power mode by setting the lowPowerModeUntil attribute as follows:

• You can manually switch on the low power mode until a specified time. For example:

  DBMCLI> ALTER DBSERVER lowPowerModeUntil="2025-01-10T23:30:00-07:00"

• You can immediately switch off the low power mode by setting lowPowerModeUntil="" or lowPowerModeUntil=NULL. For example:

  DBMCLI> ALTER DBSERVER lowPowerModeUntil=""

  You can use this setting to switch off a scheduled low power mode period or a manually started period.

• You can immediately switch off the low power mode and disable the low power mode schedule by setting lowPowerModeUntil=NEVER. For example:

  DBMCLI> ALTER DBSERVER lowPowerModeUntil=NEVER

  To re-enable the low power mode schedule, set the lowPowerModeUntil attribute to any value other than NEVER.

At any point, you can view the current lowPowerModeUntil attribute value. For example:

DBMCLI> LIST DBSERVER attributes lowPowerModeUntil

During any low power mode period, the system continually monitors itself to protect system performance. When any active workload is detected for five minutes, low power mode is automatically switched off. An active workload is characterized by any of the following:

• CPU utilization exceeds 30%.

• I/O utilization exceeds 30%.

• Throughput on the client network or RDMA Network Fabric exceeds 200 MB/sec.

When low power mode is automatically switched off because of an active workload, it remains off until the next scheduled period or until you manually switch it on.