Displaying information about threads

Use the DISPLAY THREAD TYPE(INDOUBT) command to find information about allied and database access indoubt threads. This command provides information about threads where DB2® is a participant, a coordinator, or both.

About this task

Begin general-use programming interface information.
The TYPE(INDOUBT) option tells you which systems still need indoubt resolution and provides the LUWIDs that you need to recover indoubt threads. A thread that has completed phase 1 of commit and still has a connection with its coordinator is in the prepared state and is displayed as part of the DISPLAY THREAD active report. If a prepared thread loses its connection with its coordinator, it enters the indoubt state and terminates its connections to any participants at that time. Any threads that are in the prepared or indoubt state when DB2 terminates are indoubt after DB2 restart. However, if the participant system is waiting for a commit or rollback decision from the coordinator, and the connection is still active, DB2 considers the thread active.
End general-use programming interface information.

If a thread is indoubt at a participant, you can determine whether a commit or abort decision was made at the coordinator by issuing the DISPLAY THREAD command at the coordinator as described previously. If an indoubt thread appears at one system and does not appear at the other system, the latter system backed out the thread, and the first system must therefore do the same.

  • Displaying information by location
    You can use the DISPLAY THREAD command to display thread information for particular locations.
  • Displaying information for non-DB2 locations
    Because DB2 does not receive a location name from non-DB2 locations, you must enter the LUNAME or IP address of the location for which you want to display information.
  • Displaying conversation-level information about threads
    Use the DISPLAY THREAD command with the LOCATION and DETAIL options to display information about conversation activity when distribution information is displayed for active threads.
  • Displaying threads by LUWID
    Use the optional LUWID keyword, which is valid only when DDF is started, to display threads by logical unit of work identifiers. The LUWIDs are assigned to the thread by the site that originated the thread.
  • Displaying threads by type
    Use the DISPLAY THREAD command to display threads by type. For example, you can display only the active threads that are executing a stored procedure or user-defined function.
Parent topic: Monitoring threads
Related concepts:
Output of the DISPLAY THREAD command
Related reference:
-DISPLAY THREAD (DB2)

Related information

DSNV401I