Performing group buffer pool operations
Using the OPERTUNE group buffer pool operations, you can perform I/O balancing among the Db2 subsystems in a data sharing group by changing the castout owner of a data set. The castout operations provide a way for you to force Db2 to write data to disk so that external applications can read the data sets directly. You can perform the following tasks:
- Casting out a group buffer pool
- Changing the castout owner of a data set
- Casting out a table space
- Casting out a data set
Select the Group buffer pool operations option from the Operational Assist Menu to display the Group Buffer Pool List panel, which lists all active group buffer pools.
Group Buffer Pool List panel
Command ===> ___________________________________________ Scroll ===> PAGE
Commands: ZPARMS
Select the desired group buffer pool(s). Then Press Enter.
L=GBP Dependent Table Space List
Group Buffer Class
Act Name Pages Ratio Pool Castouts Castouts
.. GBP0 1236 5 0 4
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Use this panel to perform the actions listed in the following table:
Command | Description |
|---|---|
GBP Dependent Table | List the GBP dependent table spaces for changing the castout owner, or casting out a table space or a data set |
ZPARMS | Display the Element Selection panel |
To cast out a group buffer pool using the CASTOUT GBPOOL command
Use the following syntax to issue the CASTOUT GBPOOL command:
Command syntax and parameters
Value | Description |
|---|---|
DB2ssid | Db2 subsystem ID or the name of the Db2 data sharing group to which the command applies. |
opertuneID | OPERTUNE system profile name (if OPERTUNE is running as a started task) or the batch job name (if OPERTUNE is running as a batch job). |
gbpoolID | Specify a group buffer pool ID in one of the following ranges:
|
To display the Group Buffer Pool Dependent Table Space List panel
From the Group Buffer Pool List panel, type L in the Act field next to the group buffer pool that contains the castout owner you want to change and press Enter.
The GBP Dependent Table Space List panel is displayed.
Command ===> ________________________________________________ Scroll ===> PAGE
Currently Selected GBP . . . : GBP0 Commands: FILTER
Select the desired table space(s). Then Press Enter.
L =GBP Dependent Data Set Name List
Act Catalog Name Database Name Table Space Name
.L DSNDFA DDTQDB0 DDTQTS0
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To display the Group Buffer Pool Dependent Dsname List panel
To display Group Buffer Dependent Dsname List panel, type L in the Act field next to the table space and press Enter.
Command ===> ________________________________________________ Scroll ===> PAGE
Currently Selected GBP . . . : GBP0
Currently Selected Table . . : DSNDFA DDTQDB0 DDTQTS0
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To change the castout owner of a data set
You can change the castout owner by using the CHANGECO command.
Use the following syntax to issue the CHANGECO command:
Command syntax and parameters
Value | Description |
|---|---|
DB2ssid | Db2 subsystem ID or the name of the Db2 data sharing group to which the command applies. |
opertuneID | OPERTUNE system profile name (if OPERTUNE is running as a started task) or the batch job name (if OPERTUNE is running as a batch job). |
dataSet | Specify the name of the data set for which the castout owner will be changed. |
owner | Specify the subsystem that will be the new castout owner of the specified data set. |
To cast out a table space
You can cast out a table space by using the CASTOUT TABLESPACE command.
Use the following syntax to issue the CASTOUT TABLESPACE command:
Command syntax and parameters
Value | Description |
|---|---|
DB2ssid | Db2 subsystem ID or the name of the Db2 data sharing group to which the command applies. |
opertuneID | OPERTUNE system profile name (if OPERTUNE is running as a started task) or the batch job name (if OPERTUNE is running as a batch job). |
catalog | Specify the name of the catalog for the data set that contains the table space to be cast out. |
dataSet | Specify the Db2 subsystem ID or data sharing group name of the data set that contains the table space to be cast out. |
tableSpace | Specify the name of the table space to be cast out. |
To cast out a data set
You can cast out a data set by using the CASTOUT DATASET command.
Use the following syntax to issue the CASTOUT DATASET command:
Command syntax and parameters
Value | Description |
|---|---|
DB2ssid | Db2 subsystem ID or the name of the Db2 data sharing group to which the command applies. |
opertuneID | OPERTUNE system profile name (if OPERTUNE is running as a started task) or the batch job name (if OPERTUNE is running as a batch job). |
name | The name of the data set to be cast out. |
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