GBP—Group buffer pool parameters
Use the Modify Group Buffer Pools panel or the GBP command to specify the attributes of a group buffer pool.
Modify Group Buffer Pools panel
Command ===> _________________________________________________________________
Command: CURRENT
Description . . . . . . . . : GROUP BUFFER POOL
Type the new buffer pool attribute values that you wish to change to. Then press Enter.
Group Buffer Pool Attribute Parameters
Ratio . . . . . . . . . . . _____ (1 - 255 or delta)
Classt . . . . . . . . . . . _____ (0 - 90 or delta)
GBPoolt . . . . . . . . . . _____ (0 - 90 or delta)
GBPchkpt . . . . . . . . . . _______ (1 - 999999 or delta)
Autorec . . . . . . . . . . _ (Y - N)
GBPcache . . . . . . . . . . _ (Y - N)
When you change group buffer pool parameters, the change is reflected in all Db2 subsystems in the data sharing group. These subsystems, however, may be under the control of other installations of OPERTUNE. These other OPERTUNE installations will show the correct values for the group buffer pool parameters but will not show that the parameters have been modified by OPERTUNE.
If you stop the OPERTUNE that made the changes, all Db2 subsystems in the data sharing group will revert to the original values, but the OPERTUNEs controlling these subsystems will not reflect the changes. If you make the change with the NORESET option, the other installations of OPERTUNE will show the correct values.
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). |
n | Buffer pool ID. Specify one of the following values:
|
ratio | Number of group buffer pool directory entries per data page. Specify one of the following values:
This value takes effect the next time that the buffer pool is allocated. |
classt | Castout class threshold for a page set (the percentage of the total data pages in the group buffer pool that can contain data from a specific page set). Specify one of the following values:
|
gbpoolt | Group buffer pool level threshold (percentage of the total data pages in the group buffer pool that can contain data). Specify one of the following values:
|
gbpchkpt | Group buffer pool checkpoint interval in minutes (the time between checkpoints in the group buffer pool). Specify one of the following values:
|
autorec | Automatic recovery. Indicates whether automatic recovery by Db2 takes place when a structure failure occurs or when the connectivity to the group buffer pool is lost by all Db2 members in the group. Specify one of the following values:
|
gbpcache | Group buffer pool cache. Determines whether the group buffer pool is used for caching data and cross-invalidation or just for cross-invalidation. Specify one of the following values:
|
NORESET | The changes you request remain in effect until the Db2 subsystem is cycled. |
Db2 parameter values
Field | Installation panel | CLIST parameter | ZPARM macro | ZPARM parameter |
|---|---|---|---|---|
Ratio | None | None | None | None |
Classt | None | None | None | None |
GBPoolt | None | None | None | None |
GBPchkpt | None | None | None | None |
Autorec | None | None | None | None |
GBPcache | None | None | None | None |