DB2 CPU

DB2 CPU Analysis

z/OS Db2 CPU - Best Practices

Helpful information:

Fields come from SMF records:

ZOSDB2CP - SMF 100 IFCID 1 - DSECT DSNDQWSA
ZOSDB2A1 - SMF 101 - subtype 0 (IFCID 3) and subtype 1 (IFCID 239)

Field names are noted in parenthesis after the description.

Helpful ESAMON screens/ESAMAP reports:

ZOSDB2CP - Db2 CPU Analysis - This shows information about Db2 CPU performance.
ZOSDB2A1 - Db2 Transaction CPU Analysis - This shows information about Db2 transaction CPU performance.

Using zVPS to find information for solving issues with the Db2 CPU:

ZOSDB2CP - Shows information about Db2 CPU performance.

SYSID - This shows the system name as defined in the parmlib member IEASYSxx SYSNAME.(SMF30SID)

Db2 SSID - This shows the Db2 system identifier.(SM101SSI)

Proc Name - This shows the procedure name of the corresponding address space.(QWSAPROC)

Intervl CPU % - This shows the CPU percent for the interval.

CPU Time in sec TotalCP - This shows the total CPU seconds on a GP for each address space;
this value is calculated from the following three fields: (QWSAEJST + QWSASRBT + QWSAIIPT).

CPU Time in sec TCB JobStep - This shows the CPU seconds assigned to a TCB.(QWSAEJST)

CPU Time in sec SRB NonPre - This shows the CPU seconds assigned to an SRB.(QWSASRBT)

CPU Time in sec SRB Preempt - This shows the non-zIIP CPU seconds assigned to a preemptable SRB.(QWSAPSRB)

CPU Time in sec MCPU - This shows the value of QWSAMCPU.

CPU Time in sec I/O - This shows CPU seconds for I/O interrupt processing.(QBSTIIPT)

zIIP SRB Preempt - This shows the preemptable SRB time consumed on a zIIP.(QWSAPSRB_zIIP)

ASID Dec - This shows the decimal address space number.(QWSAASID).

ASID Hex - This shows the hexadecimal address space number.(QWSAASID).

ASCB - This shows the ASCB token.(QWSAASCB).

ZOSDB2A1 - Shows information about CPU transaction performance.

SYSID - This shows the z/OS system ID.(SM101SID)

DB2 SSID - This shows the Db2 subsystem identifier.(SM101SSI)

Transaction Name - This shows the end user's transaction name.(QWHCEUTX)

Transaction Count - This shows the number of transactions executed in the interval.

Transaction Type - This shows the connection type code.(QWHCATYP)

     The current types are:
       1. TSO Foreground and background
       2. Db2 Call Attach
       3. DL/I Batch
       4. CICS Attach
       5. IMS Attach BMP
       6. IMS Attach MPP
       7. Db2 Private Protocol
       8. DRDA Protocol
       9. IMS Control Region
      10. IMS Transaction BMP
      11. Db2 Utilities
      12. RRSAF Attach

Elapsed Total - This shows the elapsed time (also known as Class 1 Elapsed Time).

Elapsed Db2 - This shows the elapsed time in Db2 (also known as Class 2 Elapsed Time).(QWACASC)

CPU Total - This shows the CPU time (also known as Class 1 CPU Time)

CPU Db2 - This shows the CPU time in Db2 (also known as Class 2 CPU Time).(QWACAJST)

CPU StPrc - This shows the Stored Procedure time on a general purpose processor.(QWACSPTT)

CPU Pkg - This shows the Package CPU time (also known as Class 7 CPU Time).(QPACTJST)

UDF Main - This shows the CPU time consumed while executing user defined functions on the main application execution unit.(QWACUDFNF_CP)

UDF Db2 - This shows the CPU time used to satisfy UDF processing requests in a Db2 stored procedure/WLM address space.(QWACUDCP)

Trigger Main - This shows the CPU time consumed while executing triggers on the main application exection unit. (QWACTRTT)

Trigger Nest - This shows the CPU time consumed while executing triggers on a nested task.(QWACTRTE)

StrProc Main - This shows the CPU time consumed while executing stored procedures on the main application execution unit.(QWACSPNF_CP)

StrProc SQL - This shows the CPU time used to satisfy stored procedure processing SQL CALL statements in a Db2 stored procedure/WLM address space.(QWACSPCP)

zIIP CPU Elig - This shows the CPU time on a standard engine for work that was eligible to run on a specialty processor.(QWACZIIP_ELIGIBLE)

zIIP CPU Main - This shows the CPU time executing on an IBM specialty engine.(QWACCCLS1Z)

zIIP CPU Db2 - This shows the CPU time in Db2 executing on an IBM specialty engine.(QWACCCLS2Z)

zIIP CPU Pkg - This shows the CPU time for package execution on an IBM specialty engine.(QPACCCLS7_zIIP)

zIIP CPU UDF - This shows the CPU time consumed while executing user defined functions on the main application execution unit on an IBM specialty engine.(QWACUDFNF_zIIP)

zIIP CPU Trig - This shows the CPU time consumed while executing triggers on the main application exection unit on an IBM specialty engine.(QWACTRTT_zIIP)

zIIP CPU StrdProc - This shows the CPU time consumed while executing user defined functions on the main application execution unit on an IBM specialty engine.(QWACSPNF_zIIP)