ISGLOCK structure request processing

Infrequently, there are situations that can cause requests to the ISGLOCK structure to be left in an incomplete state. When this occurs, resource requests for those resources that have been hung up will never complete, holding up the requesters indefinitely. The DISPLAY GRS,CONTENTION command provides information regarding resources and requesters that might be in this state. To determine if there is a problem with request processing, you should issue the command on all systems in the sysplex, because the data required to determine the condition is located on each system. When the system is running correctly, the response to the DISPLAY GRS,CONTENTION command, message ISG343I, will look as follows:

ISG343I 13.46.47 GRS STATUS 379         
[resource contention information]
NO REQUESTS PENDING FOR ISGLOCK STRUCTURE                             
[latch contention information]

When there is a potential problem, the command will indicate the resource and requesters associated with the hung resources. Potentially hung resources are noted by the indication of a delay of more than two seconds in response time. If this text does not appear, the request might still be active, and the appearance in the output is not indicative of a problem. However, if the situation persists, the number of hung requesters will increase. To correct the situation, rebuild the ISGLOCK structure with the SETXCF START,REBUILD,STRNAME=ISGLOCK. An example of the output from the DISPLAY GRS,CONTENTION command when there might be a problem is presented below:

ISG343I 13.46.47 GRS STATUS 380         
[resource contention information]
GLOBAL REQUESTS PENDING FOR ISGLOCK STRUCTURE:                     
SYSDSN   SYS1.PROD1.LINKLIB                                        
PRODTOOL 001E 007E7B68 ENQ-EXCL LOCK REQUEST AT 10/25/1999 13:59:21
THIS REQUEST IS DELAYED MORE THAN 2 SECONDS
[latch contention information]