IBM SC34-7012-01 Server User Manual


 
Coupling facility data table retained locks
Recoverable coupling facility data table records can be the subject of retained locks,
like any other recoverable CICS resource that is updated in a unit of work that
subsequently fails.
A recoverable CFDT supports indoubt and backout failures. If a unit of work fails
when backing out an update to a CFDT, or if it fails indoubt during syncpoint
processing, the locks are converted to retained locks and the unit of work is
shunted. If a CFDT record is locked by a retained lock, an attempt to modify the
record fails with the LOCKED condition. This can be returned on the following
API file control requests issued against CFDT records:
v DELETE with RIDFLD
v READ with UPDATE
v READNEXT with UPDATE
v READPREV with UPDATE
v WRITE
To resolve retained locks against CFDT records, use the CEMT INQUIRE
UOWLINK command to find the unresolved units of work associated with links to
the coupling facility data table pool containing the table. When you have found the
UOW links, take the appropriate action to resolve the link failure or force
completion of the UOWs.
The owner of the failed UOW could be another CICS region in the sysplex, and the
cause of the retained lock could be one of the following:
v The CICS region cannot resolve the UOW because its CFDT server has failed.
v The CICS region that owns the UOW has failed to connect to its CFDT server.
v The CICS region that owns the UOW cannot resynchronize with its CFDT
server.
v An indoubt failure caused by the loss of the CICS region that is coordinating a
distributed UOW.
v An indoubt failure caused by the loss of connectivity to the CICS region that is
coordinating a distributed UOW.
182 CICS TS for z/OS 4.1: Recovery and Restart Guide