Formatting global resource serialization dump data

Obtain an SVC or stand-alone dump. If you suspect that the problem might involve more than one system in the global resource serialization complex, obtain a dump for each system. Make sure dumps include the global resource serialization and XCFAS address spaces and any necessary data spaces. If you suspect a problem with a user of GRS ENQ services, then SDATA=GRS should be specified on the dump. This causes GRS to collect complex-wide information related to outstanding ENQs. If you suspect a problem with GRS itself, then you should dump both the GRS and XCF address spaces. Note that dumps taken by GRS when in Star mode for GRS problems might be multi-systems.

There are several ways to use IPCS subcommands with dumps to diagnose global resource serialization problems:

To format the dump or dumps for the diagnosis data of global resource serialization , see VERBEXIT GRSTRACE or GRSDATA in z/OS MVS IPCS Commands. See VERBEXIT GRSTRACE subcommand output for a sample report of VERBEXIT GRSTRACE. You can find a sample GRSDATA report in z/OS MVS IPCS Commands.
To combine trace data from multiple dumps, see Combining trace data from multiple systems.

GRSDATA and GRSTRACE reports can be used to view resources and requesters known to the local system.

The GRSDATA report uses SDATA=GRSQ records. The GRSTRACE report uses GRS internal control blocks from the GRS address space and includes diagnostic data and configuration information about GRS. Both reports support several filtering options to limit the amount of data returned. The GRSTRACE report also supports a DETAIL view.

When GRS is in STAR mode, GRSTRACE can only show requests from the local system. The GRSDATA report can be used to see information that includes global resources from other systems. The amount of data included depends on the GRSQ setting of the local system.

GRSDATA and GRSTRACE reports include GRS-managed Latch information at the bottom for all dumped address spaces with accessible Latch sets. See z/OS MVS IPCS Commands for more information on the GRSDATA and GRSTRACE commands.

The IPCS ANALYSIS,CONTENTION report produces GRS Latch and ENQ contention reports. In Star mode, the ENQ contention report does not report about Global ENQs. GRSTRACE and GRSDATA can provide information on all ENQ resources whether they are in contention or not. GRSDATA is the only report that can process Star mode Global ENQ information. Latch contention is only provided through IPCS ANALYSIS,CONTENTION. No reporting is provided for latches that are held but not in contention.