The Group Buffer Pool Attributes section

This report section shows group buffer pool attributes, which are retrieved from IFCID 230.

              =======     Group Buffer Pool Attributes   ======= 
 Group Buffer Pool                 GBP0       GBP2     GBP8K0    
 --------------------------- ---------- ---------- ----------    
 Allocated GBP size (4K)            768        768        768    
 Current dir.to data ratio            5          5          5    
 Class castout thresh. (%)            5          5          5    
 Class castout thresh. (#)            0          0          0		 
 Actual nbr. of dir. entrs         1450       1450        621    
 Pending dir. to data ratio           5          5          5    
 GBP castout thresh. (%)             30         30         30    
 Actual nbr. of data entrs          287        287        124    
 Checkpoint interval (min)            4          4          4    
 Autorec                            yes        yes        yes    
 Directory-entry-reclaim              0          0        318    
 Data-entry-reclaim                8154        867       1574    
 GBP cache                          yes        yes        yes    
 Total-changed                        3          2          0    
 XI-dir.-entry-reclaim                0          0        321    
 Mode                           SIMPLEX    SIMPLEX    SIMPLEX    
 Secondary-GBP                                                   
  Alloc GBP size (4K)               n/a        n/a        n/a    
  Directories entries               n/a        n/a        n/a    
  Data entries                      n/a        n/a        n/a    
 =========================== ========== ========== ==========    
⋮
Allocated GBP size (4K)
The allocated size of the group buffer pool in 4 KB blocks. Derived from the DB2® field QBGBGSZ.
Current dir. to data ratio
The current directory entry per data entry ratio. Derived from the Db2 field QBGBGR1.
Class castout thresh. (%)
The threshold at which class castout is to be initiated. It is expressed as a percentage of the group buffer pool size. Derived from the Db2 field QBGBGCT.

If the GBP castout thresholds are not set correctly, castout processing is not kept in pace with the changed pages written to the CF (coupling facility). You can either use the ALTER GROUPBUFFERPOOL command to reduce the castout thresholds, or increase the number of GBP data pages by increasing the GBP size or by reducing the GBP RATIO.

Class castout thresh. (#)
Class level castout threshold (buffer num). Derived from the Db2 field QBGBGCTN.
Actual nbr. of dir. entrs
The actual number of allocated directory entries. Derived from the Db2 field QBGBGDR.
Pending dir. to data ratio
The pending directory entry per data entry ratio. Derived from the Db2 field QBGBGR2.
GBP castout thresh. (%)
The threshold at which castout is to be initiated for the group buffer pool. It is expressed as a percentage of the size of the group buffer pool. Derived from the Db2 field QBGBGGT.
Actual nbr. of data entrs
The actual number of allocated data entries. Derived from the Db2 field QBGBGDT.
Checkpoint interval (min)
The time interval (in minutes) between successive group buffer pool checkpoints. Derived from the Db2 field QBGBGCK.
Autorec
A flag indicating how the AUTOREC option of the ALTER GROUPBUFFERPOOL command has been set. It specifies whether automatic recovery takes place in case of a structure failure or loss of connectivity of all members of the group buffer pool. Derived from the Db2 field QBGBGAS.
Directory-entry-reclaim
The number of times that a page name assignment required that a coupling facility directory entry be reclaimed (stolen). Derived from the Db2 field QBGBDRR.
Data-entry-reclaim
The number of times that a page name assignment required that a coupling facility data entry be reclaimed (stolen). Derived from the Db2 field QBGBDTR.
GBP cache
Caching attribute. Possible values are:
  • YES: The GBP is used for both data caching and cross-invalidation.
  • NO: The GBP is used only for cross-invalidation.
Total changed
The number of allocated data entries that are currently in changed state. This is a snapshot value and is not cumulative. Derived from the Db2 field QBGBTCC.
XI-dir.-entry-reclaim
The number of times that a directory entry was stolen and one or more XI signals had to be sent because the page in the directory was cached in one or more Db2 buffer pools. Derived from the Db2 field QBGBRXI.
Mode
Possible values are:
  • DUPLEX
  • SIMPLEX
Derived from the Db2 field QBGBDUP.
Secondary-GBP — Alloc. GBP size (4K)
When MODE is DUPLEX, the allocated size of the secondary group buffer pool. Derived from the Db2 field QBGBGSZ2.
Secondary-GBP — Directories entries
When MODE is DUPLEX, the number of allocated directory entries in the secondary group buffer pool. Derived from the Db2 field QBGBGDR2.
Secondary-GBP — Data entries
When MODE is DUPLEX, the number of allocated data entries in the secondary group buffer pool. Derived from the Db2 field QBGBGDT2.