Thread History Group Buffer Pool Activity

This panel provides a summary of group buffer pool usage for an individual thread.

 
________________ ZHTGBUF  VTM     O2       V550.#P SN12 11/06/13 15:33:44   2  
> Help PF1               Back PF3               Up PF7                 Down PF8 
                                                                                
>          THREAD HISTORY:  Enter a selection letter on the top line.           
                                                                                
> A-THREAD DETAIL   B-LOCK COUNTS  C-LOCK WAITS     D-GLOBAL LOCKS  E-SORT/SCAN 
> F-DYNAMIC SQL     G-SQL COUNTS   H-DISTRIBUTED    I-BUFFER POOL   *-GROUP BP  
> K-PACKAGE SUMMARY L-RES LIMIT    M-PARALLEL TASKS                             
=============================================================================== 
>                   THREAD HISTORY GROUP BUFFER POOL ACTIVITY                   
 HPLN                                                                           
+ Thread:  Plan=DSNESPCS  Connid=TSO      Corrid=MIS          Authid=MIS        
+ Attach:  TSO            DB2=SN12        MVS=PMO4                              
+ Time  :  Start=11/06/2013 15:31:46.293559     End=11/06/2013 15:32:36.252634  
+ Luwid=DEIBMIPS.IPSATN12.CC3934B34B7E                                          
 gbuf                                                                           
+ Group Buffer Pool:   ALL                                                      
+ Reads - Cross-Invalidation:             Reads - Page Not Found:               
+   Data Returned             =       0     Data Returned             =       0 
+   Data not in GBP-R/W Int   =       0     Data not in GBP-R/W Int   =       0 
+   Data not in GBP-No R/W Int=       0     Data not in GBP-No R/W Int=       0 
+ Read Hit Percentage         =     .0%   Read-to-Write Percentage    =     .0% 
+ Changed Pages Written       =       0   Clean Pages Written         =       0 
+                                                                               
+ Group Buffer Pool:   GBP0                                                     
+ Reads - Cross-Invalidation:             Reads - Page Not Found:               
+   Data Returned             =       0     Data Returned             =       0 
+   Data not in GBP-R/W Int   =       0     Data not in GBP-R/W Int   =       0 
+   Data not in GBP-No R/W Int=       0     Data not in GBP-No R/W Int=       0 
+ Read Hit Percentage         =     .0%   Read-to-Write Percentage    =     .0% 
+ Changed Pages Written       =       0   Clean Pages Written         =       0 
+                                                                               
+ Group Buffer Pool:   GBP32K                                                   
+ Reads - Cross-Invalidation:             Reads - Page Not Found:               
+   Data Returned             =       0     Data Returned             =       0 
+   Data not in GBP-R/W Int   =       0     Data not in GBP-R/W Int   =       0 
+   Data not in GBP-No R/W Int=       0     Data not in GBP-No R/W Int=       0 
+ Read Hit Percentage         =     .0%   Read-to-Write Percentage    =     .0% 
+ Changed Pages Written       =       0   Clean Pages Written         =       0 
===============================================================================

Fields

Thread identifier: This information identifies the thread to which the information in this panel applies.
Plan
The Db2 plan name of the active thread.
Connid
The Db2 connection identifier of the active thread.
Corrid
The Db2 correlation identifier of the active thread. If the correlation is not set, N/A is displayed.
Authid
The Db2 authorization identifier of the active thread.
Attach
Depending on the type of connection, the appropriate information is displayed.
Attach information is displayed only if the thread is a distributed allied thread (not for distributed database access threads).
Attachment identifier:
Connection Type
The connection type is displayed in the first field:
APPLDIR
Application directed access (data base access threads)
BATCH
Other Db2 batch threads
CALLATCH
Db2 call attach
CICS®
CICS attach
DLI
DL/I batch
IMSBMP
IMS attach BMP
IMSMPP
IMS attach MPP
IMSCTRL
IMS control region
IMSBMPB
IMS transaction BMP
RRSAF
Recoverable Resource Manager Services Attachment Facility
SYSDIR
System directed access (data base access threads)
TSO
TSO foreground and background
Utility
Utility thread
Db2
The Db2 subsystem identifier.
MVS™
The MVS system identifier.
ORIGAUTH
The original (primary) Db2 authorization identifier of the thread. This field displays only when the original identifier is different from the Authid.
Time identifier:
Start
The start date and time of this thread execution.
End
The end date and time of this thread execution.
Distributed thread identifier: The following fields are displayed if the thread has a distributed relationship with a remote Db2 subsystem.
Type
The distributed thread type.
Distributed Allied
A requesting thread; one that has issued an SQL call to a remote Db2 location.
Database Access
A responding thread; one that is serving a remote Db2 location by responding to an SQL call.
Db2=
The Db2 subsystem ID, indicating the member of the data sharing group of this thread.
Luwid
This value consists of two parts: the logical unit of work ID (luw-id) and a token. The token can be used in place of the luw-id in any Db2 command that accepts luw-id as input. Format:
luw-id=token

The luw-id consists of the network name, the originating VTAM® LUNAME, and a unique identifier (separated by periods). Thus, the Luwid field displays data like in the following example:

USCACO01.O2D22A.A1FE8E04B9D4=8
System
The originating Db2 job name and the resource manager that is the source of the thread. An additional line below the Attach line identifies the user thread, if any, being served by the system thread.

Group buffer pool information:

Group Buffer Pool
The group buffer pool ID.
Reads - Cross Invalidation: Data Returned
The number of reads to the group buffer pool required because the page in the member's buffer pool was invalidated where the data was found and returned to the member.
Reads - Page Not Found: Data Returned
The number of reads to the group buffer pool required because the page was not in the member's buffer pool where the data was found and returned to the member.
Reads - Cross Invalidation: Data not in GBP-R/W Int
The number of reads to the group buffer pool required because the page in the member's buffer pool was invalidated, where:
  • The data was not found in the group buffer pool and the member had to go to DASD to read the page
  • Other members had read/write interest in the pageset, so Db2 created a directory entry for this page if it did not already exist.
Reads - Page Not Found: Data not in GBP-R/W Int
The number of reads to the group buffer pool required because the page was not in the member's buffer pool, where:
  • The data was not found in the group buffer pool and the member had to go to DASD to read the page
  • Other members had read/write interest in the pageset, so Db2 created a directory entry for this page if it did not already exist.
Reads - Cross Invalidation: Data not in GBP-No R/W Int
The number of reads to the group buffer pool required because the page in the member's buffer pool was invalidated, where:
  • The data was not found in the group buffer pool and the member had to go to DASD to read the page
  • No other member had read/write interest in the pageset, so Db2 did not have to register the page, since another member cannot cause a cross-invalidation by updating a page.
Reads - Page Not Found: Data not in GBP-No R/W Int
The number of reads to the group buffer pool required because the page was not in the member's buffer pool, where:
  • The data was not found in the group buffer pool and the member had to go to DASD to read the page
  • No other member had read/write interest in the pageset, so Db2 did not have to register the page, since another member cannot cause a cross-invalidation by updating a page.
Read Hit Percentage
The percentage of all Reads to the group buffer pool for which the needed data was found and returned to the member.
Read-to-Write Percentage
The ratio of reads to writes expressed as a percentage for the group buffer pool.
Changed Pages Written
The number of changed pages written to the group buffer pool. Pages can be forced out before the application commits if a buffer pool threshold is reached, or when P-lock negotiation forces the pages on the vertical Deferred Write queue to be written to the group buffer pool.
Clean Pages Written
The number of clean pages written to the group buffer pool. Db2 writes clean pages for pagesets and partitions defined with GBPCACHE ALL.