Using monitors to isolate problems

All active monitors are listed here. The current measurement values are shown and plotted compared to the thresholds. The W in the middle of the graph marks the warning threshold values. All monitors with acceptable values remain on the left side of the W. Those in warning status extend to the right and are highlighted.

To start a monitor and modify an active monitor

1. On the AT view, type SM (Start Monitors) on the COMMAND line.The Start Monitor view is displayed listing all available monitor services.

   
   

   >W1 =SM================DEGQ=====*========DDMMYYYY==HH:MM:SS====MVDB2====D==198
   -                             Monitor Services                           
     Commands:  BLK (Requests)  JOURNAL (Log Display)                        
     Line CMDs: S (Select),   L (Lock),   U (unlock),   H(Help)                 
   
   CMD Service  Num    Title                        Parm Type       Area   Status
   --- -------  Actv   --------------------------   --------------  -----  ------
       #PFRQ           PREFETCH REQUESTS            (IDENTIFIER)    WKLD          
       #PRLF           I/O PRLL-FALLBACK-SEQ        (IDENTIFIER)    WKLD          
       #PRLG           I/O PRLL-GROUPS EXEC         (IDENTIFIER)    WKLD          
       #PRLR           I/O PRLL-GROUPS REDUCED      (IDENTIFIER)    WKLD          
       #PRLS           SYSPLEX PRLL QUERY FAILS     (IDENTIFIER)    WKLD          
       #PROC       3   DB2 TRANS PROCESSED          (IDENTIFIER)    WKLD          
       #RDIO           READ I/OS                    (IDENTIFIER)    WKLD          
       #REOP           REOPTIMIZATIONS              (IDENTIFIER)    WKLD          
       #SPRC           SPROCS EXECUTED              (IDENTIFIER)    WKLD          
       #SQLA           ADMINISTRATIVE STMTS         (IDENTIFIER)    WKLD          
       #SQLC           SQL STMTS PER COMMIT         (IDENTIFIER)    WKLD          
       #SQLD           DDL SQL STATEMENTS           (IDENTIFIER)    WKLD          
       #SQLM       1   DATA MANIPULATIVE SQL        (IDENTIFIER)    WKLD          
       #SUSP           SUSPENSIONS                  (IDENTIFIER)    WKLD          
       #TMO            TIMEOUTS                     (IDENTIFIER)    WKLD          
       #UPDP           UPDATE PAGE REQUESTS         (IDENTIFIER)    WKLD          
       #WRIT           WRITE IMMEDIATES             (IDENTIFIER)    WKLD          
       @CPU            AVERAGE CPU USED             (IDENTIFIER)    WKLD          
       @CPUD           AVG CPU IN DB2               (IDENTIFIER)    WKLD          
       @ELAP       1   AVG ELAPSED TIME             (IDENTIFIER)    WKLD          
       @ELCL           AVG ELAPSED FOR CLAIM WT     (IDENTIFIER)    WKLD

   Monitors look either at resources/system activity (resource monitors) or at workload activity (workload monitors). All workload monitor names start with # (for a count) or with an @ (for an average). One workload monitor can be started multiple times to look at different workloads, which can help isolate specific workload-related problems. Some resource monitors also have parameters to support multiple requests—for example, buffer pool number.

   You can scroll through the list by using the F7 and F8 keys, sort on any of the columns, or select only monitors for the area in which you are interested.

2. To select a workload monitor, type S in the CMD column next to a service.The Start Workload Monitor dialog is displayed. The following figure shows an example for the #PROC service:

   
   

                            Start Workload Monitor
   COMMAND ===>                                              SCROLL ===> CSR
                                                                     MORE: +
                          #SQLM - DATA MANIPULATIVE SQL                         
   Monitor Attributes:                                                        
   PARM     DB2XVALS     (Identifier)       START 00:09:00 (hh:mm:ss)         
   INTERVAL 00:01:00     (hh:mm:ss)         STOP           (hh:mm:ss/mins)    
   WVAL                  (Warning value)    WIF            (Intvls to 1st msg)
   WMSG                  (Log warnings to)  WIN            (Message Intervals)
   WLIM     10           (Warnings limit)   RST   HOT      (HOT,PUR,QIS)      
                                            QIS   YES      (YES/NO)           
   TITLE   DATA MANIPULATIVE SQL
   PLOTMAX                              (Maximum PLOT X-Axis value)           
   RANGES                               (1-4 Range Distr. Upper Limits)       
   LOG     NO                           (NO,ATSTOP,ATPD,ATINTVL,ATWARN)       
                                                                            
   Specify Workload Inclusion Criteria:                                               
     ICHECK    NO                      (Check Elapsed versus Interval time)    
     CONNTYPE                          (TSO, IMS, CICS, BATCH, etc.)     
     DB2PLAN   DSNREXX                                                 
     DB2AUTH   MVSKLK++                                                      
     DB2CONN                                                                 
     DB2CORR                                                                 
     DB2LOC                                                               
     DB2PKG                                                               
     DB2RTN                                                              
    The following parameters are enabled for only MVDB2 versions V12.1 and later
    Specify Workload Exclusion Criteria:                                        
     XCONNTYP  TSO                      Specify CONNTYPE or XCONNTYP, not both     
     XDB2PLAN  MVSKPLAN
     XDB2AUTH  MVSKAUTH
     XDB2CONN  MVSKCONN
     XDB2CORR  MVSKCORR
     XDB2LOC   MVSKLOC
     XDB2PKG   MVSKPKG
     XDB2RTN   MVSKRTN
   
    ENTER to accept the selection criteria
    HELP to view related help

3. Define optional workload monitor data collection parameters on the dialog by using mostly defaults:

   
   

   Parameter	Description
   PARM	You can specify any name as an ID if you want several requests for this monitor to look at different workloads.
   START	Use the default to start at the next even minute, or type a future time in the format of hh:mm:ss. Warning Important The monitors are synchronized to the even minute to make it easier for you to compare the history values that they collect.
   INTERVAL	Use the default (00:01:00) of one-minute data collection intervals.
   STOP	Use the default of no stop time, or type a time at which you want the monitor to stop in the format of hh:mm:ss, or the number of intervals (minutes).
   WVAL	A warning message is issued automatically when a sampling exceeds the monitor threshold. Type a low value so that you can see a warning. For example, if you expect 100 statements in a minute, type 50. You can change this setting to a more appropriate value later.
   WIF	Wait n intervals before issuing a warning. This parameter is optional; accept the default.
   WMSG	If you leave this parameter blank, a warning message is sent to the Journal log when sampling exceeds the monitor threshold. This can be used to trigger  EXECs. Current warnings are shown on Db2EX. Specify WTO if you want to send a message to the MVS console, or enter a TSO ID to send a message to that user.
   WIN	Wait n intervals before sending nth warning. This parameter is optional; accept the default.
   WLIM	Limits the number of warning messages that a monitor can generate By default,  writes these warning messages to the BBI Log/Journal. To change this default, see the WMSG parameter. This parameter is optional; accept the default. Warning Important Alternatively, you can specify -1 to receive an unlimited number of warning messages for a monitor at regular intervals. The default interval is 60 seconds.
   RST	Monitor the reaction if Db2 stops and is restarted. This parameter is optional; accept the default.
   QIS	Action to be taken when a target is not active This parameter is optional; accept the default.
   TITLE	Display title for the monitor service This parameter is optional; accept the default.
   PLOTMAX	Specify maximum value of X Axis on monitor plot display. This parameter is optional; accept the default.
   RANGES	Set limits for range distribution statistics on plot display. This parameter is optional; accept the default.
   LOG	Record a hardcopy plot in the BBI-SS PAS Image log. This parameter is optional; accept the default.

4. Specify workload inclusion criteria. 
   You can specify a CONNTYPE to include workload monitor data collection by connection type: BATCH, CAF, CICS, DDF, DLI, DRDA, IMS, IMSBMP, IMSCTL, IMSMPP, IMSTBMP, RRSAF, TSO, UTIL, or blank.Blank collects data for all connection types.

   Optionally, type one or more names next to DB2PLAN, DB2AUTH, DB2CONN, DB2CORR, DB2LOC, DB2PKG, and/or DB2RTN. The name can be a TSO, BATCH, DB2CALL, an IMSID, or a CICS Jobname. Leave blank for total workload.

   For an explanation of the other workload inclusion criteria, see Starting-a-monitor.

5. Specify workload exclusion criteria. For an explanation of the other workload exclusion criteria, see Starting-a-monitor.
6. Press Enter to start the monitor and return to the list of monitors.
7. Press F3 to return to the Active Monitors view (AT).
8. Press Enter repeatedly until the new monitor shows an ACTIVE status and current measurement values.(Remember, the monitors were synchronized to start at an even minute.) You might need to scroll right to see the status field.
9. Modify a monitor in warning status (highlighted).
   1. Type M (modify) next to the monitor ID to view the monitor options in effect.

   2. Modify any of the options that you can tab to.

      Warning

      Important

      If you did not start this monitor, you need special authorization to modify or purge it.

10. Choose an active monitor and change its threshold value.
    1. Type M (modify) next to the monitor ID.
    2. Set the threshold value in the WVAL field:
       • To set a maximum value, type >n
       • To set a minimum value, type < n

11. Press F3 to return to the SM view, and press F3 again to return to the AT view.Look at how the graph of the current value compared to the new threshold has changed.

    Warning

    Important

    To stop a monitor, use the Z line command.

    You now know how to start and modify monitors. Next, you will learn how to look at the data.