Analyzing deadlock information

To list deadlock victims and analyze deadlock information, use the Deadlock Victims List panel.

In a deadlock, a transaction locks record A and attempts to lock record B. However, a second transaction has already locked record B and is attempting to lock record A. Because neither transaction can continue until the other transaction releases its locks, IMS typically issues a user 777 or 123 pseudo abend for one of the transactions.

Related topics

Working-with-reports-in-the-ISPF-interface

You can use the Deadlock Victims List panel for the following purposes:

  • View a concise list of applications that were affected by deadlocks.
  • View essential information about deadlock victims, sort the list by information of interest, and locate specified data values.
  • Select deadlock victims for further research.

To list Deadlock Victims

  1. Access the Report Index File Analysis panel. For instructions, see Accessing-reports-in-the-ISPF-interface.

  2. In the Analysis option field, enter 10.The Deadlock Victims List panel is displayed:

      File  Sort  Options  Help                                                    
    -------------------------------------------------------------------------------
    Log Analyzer                Deadlock Victims List                  Row 1 of 28
    Command ===> ________________________________________________ Scroll ===> CSR  
                                                                                  
    Report index file: 'WXC.LUI.INDEX.DEAD1'                                    
    Type one or more action codes.                                                 
      S=Deadlock detail                                     Sorted by: DL#         
                                                                                  
    A  DL#    DMB    Count IMS/ESS  Tran/Job   PSB    PCB/DBD   PST                
    - ----- -------- ----- -------- -------- -------- -------- -----               
    _ 00001 DI21PART     2 I15G     APPL0028 APPL0028 DI21PART 00002               
    _ 00002 DI21PART     4 I15G     APPL0027 APPL0027 DI21PART 00004               
    _ 00003 DI21PART     3 I15G     APPL0017 APPL0017 DI21PART 00009               
    _ 00004 DI21PART     4 I15G     APPL0037 APPL0037 DI21PART 00007               
    _ 00005 DI21PART     3 I15G     APPL0028 APPL0028 DI21PART 00005               
    _ 00006 DI21PART     4 I15G     APPL0017 APPL0017 DI21PART 00001               
    _ 00007 DI21PART     4 I15G     APPL0017 APPL0017 DI21PART 00007               
    _ 00008 DI21PART     3 I15G     APPL0017 APPL0017 DI21PART 00002               
    _ 00009 DI21PART     2 I15G     APPL0027 APPL0027 DI21PART 00008               
    _ 00010 DI21PART     2 I15G     APPL0017 APPL0017 DI21PART 00001               
    _ 00011 DI21PART     2 I15G     APPL0017 APPL0017 DI21PART 00007               
    _ 00012 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00001               
    _ 00013 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00014 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00009               
    _ 00015 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00016 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00007               
    _ 00017 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00018 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00001               
    _ 00019 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00020 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00009               
    _ 00021 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00022 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00007               
    _ 00023 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00024 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00001               
    _ 00025 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00026 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00009               
    _ 00027 DI21PART     4 I15G     APPL0007 APPL0007 DI21PART 00004               
    _ 00028 DI21PART     3 I15G     APPL0018 APPL0018 DI21PART 00007               
    ****************************** Bottom of Data ********************************
    F1=Help    F3=Exit    F7=Up      F8=Down   F12=Cancel                         

    The panel provides summary information as follows:

    Field

    Description

    DL#

    The DL# field contains a sequential number that Log Analyzer assigned during the analysis job to identify this deadlock.

    DMB

    The DMB field contains the name of the data management block. This block describes the database that the transaction was attempting to access during this deadlock.

    Count

    The Count field contains the number of participants that are involved in the deadlock.

    IMS/ESS

    For each participant in the deadlock, the IMS/ESS field identifies the IMS system (or external subsystem) that was executing the transaction.

    Tran/Job

    For each participant in the deadlock, the Tran/Job field contains the name of the transaction or job.

    PSB

    For each participant in the deadlock, the PSB field contains the name of the program specification block that the transaction was using to access the database.

    PCB/DBD

    For each waiter (participant that is waiting to obtain a lock on the record) in the deadlock, the PCB/DBD field contains the name of the program communication block that the transaction was using to access the database.

    PST

    For each participant in the deadlock, the PST field contains the number of the partition specification table that describes the dependent region.

    For more information about the data in these fields, see the IMS documentation for the IMS Record Format and Print Module (DFSERA30) of the exit routine of the File Select and Formatting Print Utility (DFSERA10).

  3. (optional) To sort the list by information of interest, enter the SORT columnName command or use the Sort menu  options. For more information, see Sorting-listed-items.
  4. (optional) To locate a specified data value, enter the LOCATE data command.

  5. (optional) To view detailed information about a deadlock victim, enter S in the A (Action) field. The Deadlock Detail panel is displayed:

       File  Help                                                                                                                                                   
     ---------------------------------------------------------------------------------------------------------------------------------------------------------------
    Log Analyzer                                                        Deadlock Detail                                                  Line 00000000 Col 001 160
     Command ===>                                                                                                                                  Scroll ===> CSR  
    ************************************************************************* Top of Data **************************************************************************
    Deadlock # 00001   (# participants=002  Source=IRLM)
    timestamp=2023-188 10:08:34.2

    DMB name=DI21PART  Lock name=00028001800701D7
    key is root key for lock
    Key Dump:
    00000000   C8F6F7D4 D4C4D2F1 E6D3D2E6 F7F90000  00                                    *H67MMDK1WLKW79...               *
    Status  IMS       Tran-Job  PSB name  PCB-DBD   PST#   Rgn Call Lock  Func      State         Recovery Token           UOW-1 (Originating)      UOW-1 (Processing)
    Waiter  I15G      APPL0028  APPL0028  DI21PART  00002  MPP DLET GBIDP 22400358  03-P   Victim I15G    00001F9300000000 I15G    DD8F749E984E6601
    Holder  I15G      APPL0027  APPL0027            00004  MPP                      06-P          I15G    00001F9100000000 I15G    DD8F749E98501A81
    -----------------------------------------------------------------------------------------------------
    DMB name=DI21PART  Lock name=537A92C1800701D7
    key is root key for lock
    Key Dump:
    00000000   C8F6F7D4 D4C4D2F1 E6D3D2E6 F7F90000  00                                    *H67MMDK1WLKW79...               *
    Status  IMS       Tran-Job  PSB name  PCB-DBD   PST#   Rgn Call Lock  Func      State         Recovery Token           UOW-1 (Originating)      UOW-1 (Processing)
    Waiter  I15G      APPL0027  APPL0027  DI21PART  00004  MPP ISRT GRIDX 30400358  06-P          I15G    00001F9100000000 I15G    DD8F749E98501A81
    Holder  I15G      APPL0028  APPL0028            00002  MPP                      04-P          I15G    00001F9300000000 I15G    DD8F749E984E6601

    ************************************************************************ Bottom of Data **********************************************************************************
    F1=Help    F3=Exit    F5=RFind   F7=Up      F8=Down   F10=Left   F11=Right  F12=Cancel

    This panel displays the same information that the batch Deadlocks report contains. For more information, see Using-the-Deadlock-report or the online Help for the panel.

 

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