Viewing thread history details

Thread history details help you diagnose performance problems.

Before you begin

Before you can view thread history details, ensure that the thread history collector is running and that you have identified one or more selection criteria that you want to use to identify current or recent threads that might have performance problems.

For information about how to specify the criteria, see Using thread history.

Tip: Some thread history filters are set by default, but you can modify the filters based on your requirements. After you finish setting filters, press Enter. The Thread History Summary panel is displayed.

Procedure

  1. From the Thread History Summary panel, you can also access the following related panels:
    • BP Summ tab (Thread History Buffer Pool Summary)
    • DB2 Time Summ tab (Thread History DB2 Time Summary)
    • Lock Summ tab (Thread History Locks Summary)
    • Alt Summ tab (NTH Threads Times Summary)

    From any of these Thread Summary panels, you can drill down to view detailed information about a thread. Type a / next to the thread you want to analyze and press Enter. The Options menu is displayed.

    Figure 1. Options Menu
    Thread History Summary Options Menu
  2. Select an option by typing one of the following numbers or letters next to it, and press Enter.
    1. S Thread Detail Accounting (KDPHACCT)
    View the accounting classes 1 and 2 for a selected thread.
    2. A Thread Detail Accelerator (KDPHNACL)
    View information about accelerators for a selected thread.
    3. W Thread Detail Wait Times (KDPHWAIT)
    View information about accounting class 3 wait times for a selected thread.
    4. T Thread Detail SQL Text (KDPH0063)
    View SQL statement text and details for a selected thread.
    5. B Thread Detail Buffer Pools (KDPHBP)
    View information about buffer pools for a selected thread.
    Type S next to the buffer pool of interest to access the Db2 Thread History Detail Buffer Pool panel (KDPHBPD).
    6. G Thread Detail Group Buffer Pools (KDPHGBP)
    View information about group buffer pools for a selected thread.
    Type S next to the group buffer pool of interest to access the Db2 Thread History Detail Group Buffer Pool panel (KDPHGBPD).
    7. D Thread Detail Distributed (KDPHQLAD or KDPHQLAC)
    View information about the VTAM APPC conversations and TCP/IP conversations for a distributed (DDF) thread.
    If you select a thread that has only one location, location details are displayed in the KDPHQLAD workspace.
    If there are multiple locations associated with a selected thread, a list of locations is displayed in the KDPHQLAC summary workspace. To view details, select a location from the list. Details for the selected location are then displayed in the KDPHQLAD workspace.
    8. C Thread Detail Locks (KDPHNLOC)
    View information about the locks and the claims for a selected thread.
    9. K Thread Detail Global Locks (KDPHNGLC)
    View information about global locks for a selected thread.
    10. L Thread Detail Longest Waiters (KDPHLWAT)
    View information about the longest lock/latch waiter and the longest service task waiter.
    11. Q Thread Detail SQL Counts (KDPHSQLD)
    View SQL counts.
    12. P Thread Detail Packages (KDPHQPAC)
    View a summary of packages used in a selected thread.
    13. R Thread Detail Parallel Tasks (KDPHPTSK)
    View information about parallel tasks.
    If this thread involves parallel processing or if it invokes autonomous procedures, one of the following identifiers is displayed after the elapsed time to provide more information about this thread:
    *
    This thread is a parallel task initiated on behalf of another (originating) thread to process a query request in parallel.
    A
    This thread is an autonomous procedure rollup record.
    D
    This thread is a RRSAF/DDF rollup record due to ZPARM ACCUMACC >= 2.
    O
    This thread is the originating thread that invokes autonomous procedures.
    P
    This thread is the parent or the originating thread of the parallel tasks that are created to process a query request in parallel. Activity that is performed for this (originating) thread is reflected under the parallel tasks.
    R
    This thread is a parallel task rollup record due to ZPARM PTASKROL = YES.
    14. N Thread Detail Long Names (KDPHNAME)
    View long names associated with a selected thread.
  3. Navigate the Acct (Thread Detail Accounting), Class3 (Thread Detail Wait Times), SQLT (Thread Detail SQL Text), SQLC (Thread Detail SQL Counts), BP (Thread Detail Buffer Pools), GBP (Thread Detail Group Buffer Pools), Lock (Thread Detail Locks), PKG (Thread Detail Packages), Dist (Distributed Thread), and additional tabs to see other details about the thread.
    Tip: Use the >> tab to navigate to the next page of tabs for LWat (Thread Detail Longest Waiters), Accel (Thread Detail Accelerator), PTask (Thread Detail Parallel Tasks), Glok (Thread Detail Global Lock), or LName (Thread Detail Long Names).