Canceling threads/connections

Threads can be canceled by using the Thread/Connection List panel or by issuing the CANCEL command. Select the Cancel threads/connections option from the Operational Assist Menu to display the Thread/Connection List panel.

Use the Thread/Connection List panel to perform the actions that are listed in the following table:

Considerations when canceling threads or connections

Consider the following information before canceling threads or connections:

• You can use OPERTUNE to cancel threads, but sometimes a cancel is not possible; for example, when a thread is hung in Db2 because of logic errors. When you cancel a utility thread, you are responsible for restarting the thread and recovering the table space. OPERTUNE cannot cancel an IFI thread (monitor thread), because IFI has its own recovery routines and recovers from the cancel.
• OPERTUNE cannot cancel threads that have their own ESTAE recovery logic. If you try to cancel a thread and it appears that the attempt has failed, verify whether an accounting record for the thread termination was created, followed by a recovery of the thread.
• If all of the connection threads for the CICS attachment facility are canceled, you need to start the CICS attachment facility using the DSNC STRT command.
• If a connection thread for IMS is canceled, you need to start the IMS connection using the /START command.
• OPERTUNE must run at a dispatching priority higher than any Db2-allied address spaces. If it does not, cancel requests may not get the resources necessary for completion. You can cancel connections and threads in some allied address spaces. Cancel thread results for Db2 summarize the expected results when canceling a thread or a connection.

To cancel a thread or connection, perform the following steps:

1. On the Thread/Connection List panel, type one of the following commands:
   
   • C in the Act field next to the connection or thread you want to cancel
   • CS in the Act field next to the connection or thread you want to cancel
   • CANCEL ALL on the Command line
     You will need to filter the threads. See Filtering threads.
   • CANCEL ALL SYNCH on the Command line
     You will need to filter the threads. See Filtering threads.
2. Press Enter.
3. Issue the command from the Command Confirmation panel by typing 1 in the selection field and pressing Enter. To cancel the command, type 2 in the selection field and press Enter.

Filtering threads

If the list of threads or connections on the Thread/Connections panel is too long, or you want to use the CANCEL ALL or CANCEL ALL SYNC command on a group of threads, you must filter the threads.

1. Type FILTER on the Command line and press Enter.

   Use the Thread/Connection Filter Specifications Panel to filter the display of threads or connections in the following ways:

   • 
     
     • Connection name
     • Correlation ID
     • Authorization ID
     • Plan name
     • Address space ID
     • Thread status

   DDTG DBI1 Thread/Connection Filter Specifications
   Command ===> _________________________________________________________________
   
   Filter Information
   Connection name . . . . . . ________
   Correlation id . . . . . . .____________
   Authorization id . . . . . .________
   Plan name . . . . . . . . . ________
   Address space id . . . . . . ____
   Thread status . . . . . . . ___ (D,DI,N,PT,Q,QD,QT,RA,RD,RN,RQ,SP,SW,T,TN,TR
    followed by optional '*')
2. Type the information (in uppercase or lowercase) that you want to use to filter the threads into the appropriate fields, and press Enter. You can use wildcards as follows:

• 
  
  • ? can be substituted for any single character
  • * can be substituted for one or more characters at the end of a specification

You will be returned to the Thread/Connection List panel, and the threads or connections will be filtered according to your specifications.

Canceling threads or connections using the CANCEL command

The CANCEL command can be issued through the modify command as follows:

IN(DB2ssid@opertuneID) CANCEL