Question & Answer
Question
The Dispatcher domain in your CICS Transaction Server for z/OS (CICS TS) dump shows tasks waiting on resource LMQUEUE. This means tasks are waiting for a lock. You would like to know, how can you tell which lock is needed and which task currently owns the lock?
Answer
Format the Lock Manager summaries with VERBX DFHPDxxx 'LM=1' (where xxx is your release level of CICS like 750 for CICS TS 6.2).
Do a FIND command on 'WAIT' to find the Lock Wait Queue.
Here is an example of a Lock Wait Queue in a dump:
The only lock being waited on in this example is the DUDATSET lock (Transaction dump dataset lock). The 6 tasks above (identified by their TAS address in the OWNER column) are waiting for the lock.
Once you know the name of the lock being waited on, go back to the top of the formatted Lock Manager output and do a FIND command on 'ALLOCATED'. This should bring you to the Allocated Locks section so you can see the header information for the columns. Then search on the name of the lock your tasks are waiting for.
Here is an example of the information from the Allocated Locks section regarding the DUDATSET lock:
The owner of the DUDATSET lock is identified by the OWNER column. The address 16DDF900 is the address of a Kernel TAS control block representing the owner. If you do a FIND command on the TAS address in the Kernel domain (VERBX DFHPDxxx 'KE=1'), you should see the owner of the lock. In this case, a search on the TAS address "16DDF900" identifies the owner of the DUDATSET lock as BIGD task # 37639:
Related Information
Product Synonym
CICS/TS CICSTS CICS TS CICS Transaction Server
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Document Information
Modified date:
05 January 2026
UID
dwa1167939