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Viewing detail event statistics


There is another level of trace data available for a detail trace. It shows all traced events for a thread in chronological sequence.

To see the detail event statistics

  1. On STRAC, on the EXPAND line, navigate to the DETAIL option and press Enter.You can follow the sequence of events during thread processing using the DTRAC (Detail Trace Entry) display.

    BMC Software --------------  DETAIL TRACE ENTRY --------------PERFORMANCE MGMT
    SERV ==> DTRAC           INPUT    10:21:48  INTVL=> 3  LOG=> N  TGT==> DB2G
    PARM ==> TEST3,SEQ=000017,LEVEL=2              ROW     1 OF    35 SCROLL=> CSR
    EXPAND:  LINESEL(DETAIL), HISTORY
    START: 09:17:11 AUTH: JEK1     PLAN: DSNTIB21 CORR: DB221REQ     CONN: BATCH
    ==============================================================================
        EVENT        AT     ELAPSED     CPU   DETAIL
    -------------- -------- -------- -------- -----------------------------------
    CREATE-THD        0.000    45 ms 4,492 us
     PLAN-ALLOC       0.045                    ISOLATION=CS ACQ=USE   REL=COMMIT
    PKG-ALLOC         0.065                   *DSNESPCS ISO=CS ACQ=USE   REL=COMIT
    PREPARE   350     0.069 1,361 ms    26 ms *RC(   0) C=DT         D/X   PS(  10)
     SQL-TEXT         0.070                   *TYPE=DYNAMIC  TEXT=SELECT * FROM DS+
     EXPLAIN          0.078                   *PLAN=DSN8IC22 COST(4.6)
     EDM-REQ          1.302   123 ms 3,964 us  DB=00000258
    OPEN      524     1.489   204 us   202 us *RC(   0) C=DT
    FETCH     532     1.489 2,058 ms 6,247 us *RC(   0) C=DT         D/X   PS(   2)
     OPEN-TS          2.235                    DB=DSN8D21A TS=DSN8S21D
     OPEN-TS          3.352                    DB=DSN8D21A TS=XDEPT3
    FETCH     532     3.549    35 ms   441 us *RC(   0) C=DT         D/X
    FETCH     532     3.615   354 us   353 us *RC(   0) C=DT         D/X
    FETCH     532     3.616   335 us   335 us *RC(   0) C=DT         D/X
    FETCH     532     3.620   354 us   353 us *RC(   0) C=DT         D/X
    FETCH     532     3.621   386 us   387 us *RC(   0) C=DT         D/X
    FETCH     532     3.672   386 us   387 us *RC(   0) C=DT         D/X
    FETCH     532     3.673   337 us   337 us *RC(   0) C=DT         D/X

    The number and type of events shown depend on how much you decided to trace (more events, more overhead). The simplest detail trace captures only the major events and exceptions in the life of the thread. This trace also has SQL, SCANS, and IO.

    Subordinate events are indented in the display. Whenever possible, nesting at different levels is provided, although this nesting is somewhat dependent on the sequence in which the IFCIDs are received.

    Look at the first event, CREATE-THD.

    Events like this example, with start and end trace records, are matched and displayed on one line with relative start time, elapsed, and CPU times. Events that occur within another event (like I/O for a scan) are indented.

    Look at the PARM field.

    The SEQ number is the same as that shown on the Summary display (STRAC). But now there is a new parameter of LEVEL=2. With this parameter you can widen or narrow your view of the traced events. Level 2 shows you the major events (for example, the first event you see is probably PLAN-ALLOCation) and SQL.

  2. To see only the SQL statements, change the level to 1.PARM ==> traceid ,SEQ= nnnnnn , LEVEL=1

    Browse through the SQL statements to find one you want to know more about.

  3. Move to that statement and press F7 to scroll it to the top (SCROLL => CSR).
  4. To see SCANS and I/O, change the level to 3 .PARM ==> traceid ,SEQ= nnnnnn , LEVEL=3

    The events always remain in chronological sequence, and the event at the top of the screen remains there. Now you can see all of the events that occurred in processing the SQL statement–index scans, data scans, table space opens, sorts, dynamic SQL text and EXPLAIN data, I/O, and so on.

  5. Move the cursor to an SQL statement and press Enter.The statistics for the single SQL statement are available in a pop-up display whenever you need them, but are out of the way when browsing the events.

    BMC SOFTWARE --------------   DETAIL TRACE ENTRY    -----------PERFORMANCE MGMT
    SERV ==> DTRAC            INPUT   13:16:40  INTVL=> 3  LOG=> N  TGT==> WTNDEEO
    PARM ==> TEST,SEQ=2,LEVEL=2                          ROW 1 OF 33 SCROLL=> CSR  
    EXPAND:  EXPLAIN                                                               
    START: 12:57:19 AUTH: BOLWTN1  PLAN: DSNESPRR CORR: BOLWTN1      CONN: TSO     
    ===============================================================================
        EVENT        AT     ELAPSED     CPU   DETAIL                               
    -------------- -------- -------- -------- -------------------------------------
    OPEN      264     0.151   214 ms    25 ms *RC(   0) C=C1         D/X   PS(4006)
    ===============================================================================
    CURSOR:     C1                                                                 
    LOCATION:   DEEO                                                               
    COLLECTION: DSNESPRR                                                           
    PACKAGE:    DSNESM68                                                           
    SQL EXPANSION RSN: N/A                                                         
    CURSOR SCROLLABILITY: NO   SENSITIVITY: UNSPECIFIED  RESULT TYPE: UNSPECIFIED  
                                         INDEX SEQ-DATA                            
                                      -------- --------                            
    ROWS PROCESSED ALL TYPES             2,000    2,001                            
    ROWS PROCESSED CORRECT TYPE          1,999        1                            
    ROWS QUALIFIED BY DM (STAGE 1)           0    2,001                            
    ROWS QUALIFIED BY RDS (STAGE 2)          0    1,001                            
    ROWS INSERTED                            0        0                            
    ROWS UPDATED                             0        0                            
    ROWS DELETED                             0        0                            
    PAGES SCANNED                        2,004    2,002                            
    REFERENTIAL INTEGRITY PROCESSING:                                              
     PAGES SCANNED                           0        0                            
     ROWS DELETED/SET NULL                   0        0                            
    LOB - PAGES SCANNED                      0        0                            
        - PAGES UPDATED                      0        0                            
    ROWS SKIPPED - INCOMPATIBLE LOCK                                               

    Any event that has an asterisk at the beginning of the DETAIL column has a pop-up display. The detail column shows the most important data, but many trace records have more information available. This data varies by event type. For example, for an SQL statement, you see the return code, cursor, indicators about data access (Data/Index/Work = D/X/W), and pages scanned.

    You have already seen the SQL pop-up display; the same row/page statistics are available per scan. Some other important pop-up displays are:

    Pop-up display

    Description

    BIND-TEXT

    For DB2 Version 7.1 and earlier, text of dynamic SQL (also static SQL if BIND traced)

    EXPLAIN

    EXPLAIN data for dynamic SQL (also from BIND)

    LOCK-SUMMARY

    Summary of locks held per page set

    TIMEOUT/ DEADLOCK

    Lock contention events that cause a SQL statement or thread to fail

    RIDLIST

    Statistics on RID list processing, success, or failure

    SQL-TEXT

    Text of dynamic SQL (also static SQL if BIND traced)

  6. Press F3 until you return to the LTRAC list of thread entries.

 

Tip: For faster searching, add an asterisk to the end of your partial query. Example: cert*