VSAM Analysis situations

The predefined situations in this category monitor the status of VSAM data sets. The description and formula for these situations follow.

CICSplex_VSAMStrUse_Warning
Warning threshold exceeded for VSAM string usage.

Use LSR pools so that strings and buffers are shared for all files. LSR can greatly reduce the total I/O and CPU usage in your system. If there are no evident problems, consider increasing the number of strings in the FCT.

Formula

If 
 the value of the attribute VSAM_Strings_Percent_in_Use is greater than 85 
and 
 the value of the attribute VSAM_Strings_Percent_in_Use is less than or equal to 100
CICSplex_VSAMStrUse_Critical
Critical threshold exceeded for VSAM string usage.

Use LSR pools so that strings and buffers are shared for all files. LSR can greatly reduce the total I/O and CPU usage in your system. If there are no evident problems, consider increasing the number of strings in the FCT.

Formula

If 
 the value of the attribute VSAM_Strings_Percent_in_Use is greater than 100
CICSplex_VSAMStrWait_Warning
Warning threshold exceeded for VSAM string waits.

Consider using LSR pools so that strings and buffers are shared by files. LSR can greatly reduce the total I/O and CPU usage in your CICS region. Use the Transaction Analysis report to determine whether there is a problem that is preventing tasks from completing in a timely manner. For example, tasks can be waiting for an enqueue or CICS can be short-on-storage. If you determine that there is no bottleneck and the problem persists, consider increasing the number of VSAM strings.

Formula

If 
 the value of the attribute VSAM_String_Waits is greater than 3 
and 
 the value of the attribute VSAM_String_Waits is less than or equal to 7
CICSplex_VSAMStrWait_Critical
Critical threshold exceeded for VSAM string waits.

Consider using LSR pools so that strings and buffers are shared by files. LSR can greatly reduce the total I/O and CPU usage in your CICS region. Use the Transaction Analysis report to determine whether there is a problem that is preventing tasks from completing in a timely manner. For example, tasks can be waiting for an enqueue or CICS can be short- on-storage. If you determine that there is no bottleneck and the problem persists, consider increasing the number of VSAM strings.

Formula

If 
 the value of the attribute VSAM_String_Waits is greater than 7
CICSplex_VSAMWaitvIO_Warning
Warning threshold exceeded for VSAM waits versus I/O.

If a higher level of activity against the data set has increased string waits, consider increasing the number of strings that are defined for the named data set. Use LSR pools so that files share buffers and strings. LSR can reduce the total I/O and CPU usage in your CICS system. If a data set is defined in an LSR pool, demand for strings can be reduced as a result of successful buffer lookasides.

Formula

If 
 the value of the attribute Percent_Waits_Versus_I/O is greater than 3 
and 
 the value of the attribute Percent_Waits_Versus_I/O is less than or equal to 5
CICSplex_VSAMWaitvIO_Critical
Critical threshold exceeded for VSAM waits versus I/O.

If a higher level of activity against the data set has increased string waits, consider increasing the number of strings that are defined for the named data set. Use LSR pools so that files share buffers and strings. LSR can reduce the total I/O and CPU usage in your CICS system. If a data set is defined in an LSR pool, demand for strings can be reduced as a result of successful buffer lookasides.

Formula

If 
 the value of the attribute Percent_Waits_Versus_I/O is greater than 5
CICSplex_VSAMDataCA_Warning
Warning threshold exceeded for VSAM data CA splits.

Reorganize the file as soon as possible. If splits continue to occur at a frequent rate, consider redefining the FREESPACE options to reduce split activity.

Formula

If 
 the value of the attribute Data_CA_Splits_in_Last_Hour is greater than 1 
and 
 the value of the attribute Data_CA_Splits_in_Last_Hour is less than or equal to 2
CICSplex_VSAMDataCA_Critical
Critical threshold exceeded for VSAM data CA splits.

Reorganize the file as soon as possible. If splits continue to occur at a frequent rate, consider redefining the FREESPACE options to reduce split activity.

Formula

If 
 the value of the attribute Data_CA_Splits_in_Last_Hour is greater than 2
CICSplex_VSAMDataCI_Warning
Warning threshold exceeded for VSAM data CI splits.

Continued CI splits indicate that a CA split can occur soon. CA splits can take a long time to complete, so try to reorganize the file before the CA split occurs. Large numbers of CI splits can indicate that FREESPACE can have to be adjusted.

Formula

If 
 the value of the attribute Data_CI_Splits_in_Last_Hour is greater than 4 
and 
 the value of the attribute Data_CI_Splits_in_Last_Hour is less than or equal to 10
CICSplex_VSAMDataCI_Critical
Critical threshold exceeded for VSAM data CI splits.

Continued CI splits indicate that a CA split can occur soon. CA splits can take a long time to complete, so try to reorganize the file before the CA split occurs. Large numbers of CI splits can indicate that FREESPACE can have to be adjusted.

Formula

If 
 the value of the attribute Data_CI_Splits_in_Last_Hour is greater than 10
CICSplex_VSAMDataExt_Warning
Warning threshold exceeded for VSAM data extents.

Consider increasing the primary allocation for the data component of the file.

Formula

If 
 the value of the attribute Data_Extents_in_Last_Hour is greater than 1 
and 
 the value of the attribute Data_Extents_in_Last_Hour is less than or equal to 2
CICSplex_VSAMDataExt_Critical
Critical threshold exceeded for VSAM data extents.

Consider increasing the primary allocation for the data component of the file.

Formula

If 
 the value of the attribute Data_Extents_in_Last_Hour is greater than 2
CICSplex_VSAMNdxCA_Warning
Warning threshold exceeded for VSAM index CA splits.

Reorganize the file as soon as possible. If splits continue to occur at a frequent rate, consider redefining the FREESPACE options to reduce split activity.

Formula

If 
 the value of the attribute Index_CA_Splits_in_Last_Hour is greater than or equal to 1
CICSplex_VSAMNdxCA_Critical
Critical threshold exceeded for VSAM index CA splits.

Reorganize the file as soon as possible. If splits continue to occur at a frequent rate, consider redefining the FREESPACE options to reduce split activity.

Formula

If 
 the value of the attribute Index_CA_Splits_in_Last_Hour is greater than or equal to 1
CICSplex_VSAMNdxCI_Warning
Warning threshold exceeded for VSAM index CI splits.

Continued CI splits indicate that a CA split can occur soon. CA splits can take a long time to complete, so try to reorganize the file before the CA split occurs. Large numbers of CI splits can indicate that FREESPACE can have to be adjusted.

Formula

If 
 the value of the attribute Index_CI_Splits_in_Last_Hour is greater than or equal to 1
CICSplex_VSAMNdxCI_Critical
Critical threshold exceeded for VSAM index CI splits.

Continued CI splits indicate that a CA split can occur soon. CA splits can take a long time to complete, so try to reorganize the file before the CA split occurs. Large numbers of CI splits can indicate that FREESPACE can have to be adjusted.

Formula

If 
 the value of the attribute Index_CI_Splits_in_Last_Hour is greater than or equal to 1
CICSplex_VSAMNdxExt_Warning
Warning threshold exceeded for VSAM index extents.

Consider increasing the primary allocation for the index component of the file.

Formula

If 
 the value of the attribute Index_Extents_in_Last_Hour is greater than or equal to 1
CICSplex_VSAMNdxExt_Critical
Critical threshold exceeded for VSAM index extents.

Consider increasing the primary allocation for the index component of the file.

Formula

If 
 the value of the attribute Index_Extents_in_Last_Hour is greater than or equal to 1
CICSplex_VSAMRLSTimeout_Warning
Warning threshold exceeded for VSAM RLS timeouts.

Investigate tasks that can be holding an RLS lock for an excessive a mount of time. The online history component of Tivoli OMEGAMON XE for CICS on z/OS can be used to identify transactions that have been abnormally terminated by CICS because of VSAM timeout conditions (abend code AFCV). If the lock activity is determined to be normal, consider increasing the DTIMOUT value for transactions that use the file, or the FTIMEOUT value defined to CICS.

Formula

If 
 the value of the attribute RLS_Timeouts_in_Last_Hour is greater than 1
and 
 the value of the attribute RLS_Timeouts_in_Last_Hour is less than or equal to 20
CICSplex_VSAMRLSTimeout_Critical
Critical threshold exceeded for VSAM RLS timeouts.

Investigate tasks that can be holding an RLS lock for an excessive a mount of time. The online history component of Tivoli OMEGAMON XE for CICS on z/OS can be used to identify transactions that have been abnormally terminated by CICS because of VSAM timeout conditions (abend code AFCV). If the lock activity is determined to be normal, consider increasing the DTIMOUT value for transactions that use the file, or the FTIMEOUT value defined to CICS.

Formula

If 
 the value of the attribute RLS_Timeouts_in_Last_Hour is greater than 20

See also the CICSplex VSAM Analysis attribute group.