Logstream statistics

This section contains the following statistics:

Logstream: Global statistics

These statistics fields contain the global data collected by the log manager domain. For more information on logging and journaling, see Logging and journaling: performance considerations, and Interpreting journalname and log stream statistics.

These statistics can be accessed online using the EXEC CICS® COLLECT STATISTICS STREAMNAME command and are mapped by the DFHLGGDS DSECT. For programming information about the EXEC CICS COLLECT STATISTICS command, see the CICS System Programming Reference manual.

Table 84. Logstream: Global statistics
DFHSTUP name Field name Description
Activity Keypoint Frequency (AKPFREQ) LGGAKPFREQ is the current activity keypoint trigger value, which is the number of logging operations between the taking of keypoints. This is the AKPFREQ value specified in the SIT, or as an override, or changed dynamically using CEMT SET SYSTEM AKP(value) or EXEC CICS SET SYSTEM AKP(fullword binary data-value) commands.

Reset characteristic: not reset

 

Activity Keypoints Taken LGGAKPSTKN is the number of activity keypoints taken.

Reset characteristic: reset to zero

 

Log Deferred Force (LGDFINT) Interval (msec) LGGLGDEFER is the current log deferral interval, which is the period of time used by CICS Log Manager when determining how long to delay a forced journal write request before invoking the MVS™ system logger. This is the LGDFINT value specified in the SIT, or as an override, or changed dynamically using CEMT SET SYSTEM LOGDEFER(value) or EXEC CICS SET SYSTEM LOGDEFER(halfword binary data-value) commands.

Reset characteristic: not reset

 

Logstream: Resource statistics

These statistics fields contain the resource data collected by the log manager domain. For more information on logging and journaling, see Logging and journaling: performance considerations, and Interpreting journalname and log stream statistics.

These statistics can be accessed online using the EXEC CICS COLLECT STATISTICS STREAMNAME command and are mapped by the DFHLGSDS DSECT. For programming information about the EXEC CICS COLLECT STATISTICS command, see the CICS System Programming Reference manual.

Table 85. Logstream: Resource statistics
DFHSTUP name Field name Description
Log Stream Name LGSTRNAM is the logstream name.

Reset characteristic: not reset

 

System Log LGSSYSLG indicates if the logstream forms part of the System Log.

Reset characteristic: not reset

 

Structure Name LGSSTRUC is the coupling facility (CF) structure name for the logstream. The structure name is only applicable to coupling facility type logstreams.

Reset characteristic: not reset

 

Max Block Length LGSMAXBL is the maximum block size allowed by the MVS Logger for the logstream.

Reset characteristic: not reset

 

DASD Only LGSDONLY indicates the type of logstream. If set to 'YES' the logstream is of type DASDONLY. If set to 'NO' the logstream is of type coupling facility (CF).

Reset characteristic: not reset

 

Retention Period LGSRETPD is the logstream retention period (in days) that the data must be kept before it can be physically deleted by the MVS Logger.

Reset characteristic: not reset

 

Auto Delete LGSAUTOD is the log data auto delete indicator. If set to 'YES' the MVS Logger automatically deletes the data as it matures beyond the retention period, irrespective of any logstream delete calls. If set to 'NO' the data is only deleted when a logstream delete call is issued and the data has matured beyond the retention period.

Reset characteristic: not reset

 

Delete Requests LGSDELETES is the number of DELETEs of blocks of data from the logstream. For non-system logs, the report will show 'N/A' here, as CICS does not issue Log Delete requests against non-system logs.

Reset characteristic: reset to zero

 

Query Requests LGSQUERIES is the number of queries that CICS made to check the status of the logstream.

Reset characteristic: reset to zero

 

Logstream: Request statistics

These statistics fields contain the request data collected by the log manager domain.

These statistics can be accessed online using the EXEC CICS COLLECT STATISTICS STREAMNAME command and are mapped by the DFHLGSDS DSECT. For programming information about the EXEC CICS COLLECT STATISTICS command, see the CICS System Programming Reference manual.

Table 86. Logstream: Request statistics
DFHSTUP name Field name Description
Log Stream Name LGSTRNAM is the logstream name.

Reset characteristic: not reset

 

Write Requests LGSWRITES is the number of WRITEs of blocks of data to the logstream.

Reset characteristic: reset to zero

 

Bytes Written LGSBYTES is the total number of bytes written to the logstream

Reset characteristic: reset to zero

 

Buffer Appends LGSBUFAPP is the number of occasions on which a journal record was successfully appended to the current logstream buffer.

Reset characteristic: reset to zero

 

Waits Buff Full LGSBUFWAIT is the total number of attempts made to append a journal record to the current logstream buffer while the buffers were logically full. This situation arises when the current logstream buffer has insufficient space to accommodate the journal record, and I/O is already in progress for the alternate logstream buffer.

Reset characteristic: reset to zero

 

Current Frce Wtrs LGSCUFWTRS is the current number of tasks suspended whilst requesting a flush of the logstream buffer currently in use.

Reset characteristic: not reset

 

Peak Frce Wtrs LGSPKFWTRS is the peak number of tasks suspended whilst requesting a flush of the logstream buffer currently in use.

Reset characteristic: reset to current

 

Total Force Wts LGSTFCWAIT is the total number of tasks suspending whilst requesting a flush of the logstream buffer currently in use.

Reset characteristic: reset to zero

 

Browse Starts LGSBRWSTRT is the number of BROWSE operations started on the logstream. For non-system log logstreams, the report will show 'N/A' here, as you cannot browse these.

Reset characteristic: reset to zero

 

Browse Reads LGSBRWREAD is the number of READs of blocks of data from the logstream. For non-system log logstreams, the report will show 'N/A' here, as you cannot browse these.

Reset characteristic: reset to zero

 

Retry Errors LGSRTYERRS is the number of occasions on which MVS system logger retryable errors occurred when a block of data was being written to the logstream.

Reset characteristic: reset to zero

 

Logstream: Summary global statistics

Summary statistics are not available online.

These statistics fields contain the logstream summary global data.

Table 87. Logstream: Summary global statistics
DFHSTUP name Description
Activity Keypoint Frequency (AKPFREQ) is the last activity keypoint trigger value, which is the number of logging operations between the taking of keypoints. This is the last AKPFREQ value as specified in the SIT, or as an override, or changed dynamically using CEMT SET SYSTEM AKP(value) or EXEC CICS SET SYSTEM AKP(fullword binary data-value) commands.

 

Total Activity Keypoints Taken is the total number of activity keypoints taken.

 

Log Deferred Force (LGDFINT) Interval (msec) is the last log deferral interval, which is the period of time used by CICS Log Manager when determining how long to delay a forced journal write request before invoking the MVS system logger. This is the last LGDFINT value that was specified in the SIT, or as an override, or changed dynamically using CEMT SET SYSTEM LOGDEFER(value) or EXEC CICS SET SYSTEM LOGDEFER(halfword binary data-value) commands.

 

Logstream: Summary resource statistics

Summary statistics are not available online.

These statistics fields contain the logstream summary resource data.

Table 88. Logstream: Summary resource statistics
DFHSTUP name Description
Log Stream Name is the logstream name.

 

System Log indicates if the logstream forms part of the System Log.

 

Structure Name is the coupling facility (CF) structure name for the logstream. The structure name is only applicable to coupling facility type logstreams.

 

Max Block Length is the maximum block size allowed by the MVS Logger for the logstream.

 

DASD Only indicates the type of logstream. If set to 'YES' the logstream is of type DASDONLY. If set to 'NO' the logstream is of type coupling facility (CF).

 

Retention Period is the logstream retention period (in days) that the data must be kept before it can be physically deleted by the MVS Logger.

 

Auto Delete is the log data auto delete indicator. If set to 'YES' the MVS Logger automatically deletes the data as it matures beyond the retention period, irrespective of any logstream delete calls. If set to 'NO' the data is only deleted when a logstream delete call is issued and the data has matured beyond the retention period.

 

Log Delete Requests is the total number of DELETEs of blocks of data from the logstream. For non-system logs, the report will show 'N/A' here, as CICS does not issue Log Delete requests against non-system logs.

 

Log Query Requests is the total number of queries that CICS made to check the status of the logstream.

 

Logstream: Summary request statistics

Summary statistics are not available online.

These statistics fields contain the logstream summary request data.

Table 89. Logstream: Summary request statistics
DFHSTUP name Description
Log Stream Name is the logstream name.

 

Write Requests is the total number of WRITEs of blocks of data to the logstream.

 

Bytes Written is the total number of bytes written to the logstream.

 

Buffer Appends is the total number of occasions on which a journal record was successfully appended to the current logstream buffer.

 

Waits Buffer Full is the total number of attempts made to append a journal record to the current logstream while the buffers were logically full.

 

Peak Force Wtrs is the peak number of tasks suspended whilst requesting a FLUSH of the logstream buffer currently in use.

 

Total Force Waits is the total number of tasks suspended whilst requesting a FLUSH of the logstream buffer currently in use.

 

Log Browse Starts is the total number of BROWSE operations started on the logstream. For non-system log logstreams, the report will show 'N/A' here, as you cannot browse these.

 

Log Browse Reads is the total number of READs of blocks of data from the logstream. For non-system log logstreams, the report will show 'N/A' here, as you cannot browse these.

 

Retry Errors is the total number of occasions on which MVS system logger retryable errors occurred when a block of data was being written to the logstream.

 

Related reference
Back to full list of statistics and DFHSTUP reports
Appendix A. CICS statistics tables
Interpreting these statistics
Interpreting journalname and log stream statistics
DFH0STAT reports for these statistics
Logstreams Report
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