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v Wait for temporary storage data set extension
v Wait for shared temporary storage
v Wait for shared temporary storage pool
v Wait for file string
v Wait for file buffer
v Wait for LSRPOOL string.
An exception record is created each time any of the resources covered by
exception class monitoring becomes constrained by system bottlenecks. If
performance data is also being recorded, it keeps a count of the number of
exception records generated for each task. The exception records can be linked to
the performance data by the transaction identifier in both records.
This data is intended to help you identify constraints that affect the performance of
your transaction. The information is written to a SMF data set as soon as the task
that was originally constrained has been released.
You can enable exception-class monitoring by coding MNEXC=ON (together with
MN=ON) in the SIT. Alternatively you can use, either the CEMT command (CEMT
SET MONITOR ON EXCEPT) or EXEC CICS SET MONITOR STATUS(ON)
EXCEPTCLASS(EXCEPT).
How performance and exception class data is passed to SMF
Performance class records and exception class records are not written to SMF in
the same way by CICS monitoring.
Performance data records are written to a performance record buffer, which is
defined and controlled by CICS, as they are produced. The performance records
are passed to SMF for processing when the buffer is full, when the performance
class of monitoring is switched off, and when CICS itself quiesces. When Monitoring
itself is deactivated or when there is an immediate shutdown of CICS, the
performance records are not written to SMF and the data is lost.
Exception records are passed directly to SMF when the exception condition
completes. Each exception record describes one exception condition. You can link
performance records with their associated exception records by matching the value
of the TRANNUM field in each type of record; each contains the same transaction
number.
Controlling CICS monitoring
When CICS is initialized, you switch the monitoring facility on by specifying the
system initialization parameter MN=ON. MN=OFF is the default setting. You can
select the classes of monitoring data you want to be collected using the MNPER,
MNEXC, and MNEVE system initialization parameters. You can request the
collection of any combination of performance class data, exception class data, and
SYSEVENT data. The class settings can be changed whether monitoring itself is
ON or OFF. For guidance information about system initialization parameters, refer to
the
CICS System Definition Guide
.
monitoring—introduction
662
CICS TS for OS/390: CICS Customization Guide