The fields in this group give numbers and percentages that tell how much activity has taken place in the processing of a data or index component. The statistics in the catalog are updated when the data set is closed. Therefore, if an error occurs during CLOSE, the statistics might not be valid.

If the data set has not been properly closed, the statistics are not updated and will therefore be incorrect. Once the data set is properly closed after a previous close failure, a LISTCAT of the data set will show these statistics as invalid. VERIFY cannot correct these statistics. To correct these statistics, you can either use the EXPORT and IMPORT commands or you can REPRO the data set to a new data set. When using compressed VSAM data sets, REPRO should specify the REPLACE option to ensure that the correct statistics are calculated.

The statistics may also not be correct if the data set was open for update in more than one address space at the same time. Depending on the processing occurring (especially with inserts and deletes) and if the data set extends you may not see all the statistics properly reflected. In some cases the statistics will not include all occurrences and depending on the sequence of processing the number of logical records in the data set may be incorrect. In some cases this may show as a very large value for the number of logical records which usually indicates that at some point the counter for the number of logical records has gone negative.

COMP-USER-DATA-SIZE—The total length of data after compression. If the data lengths are too large to be presented in decimal, they are presented in hexadecimal format.

FREESPACE-%CI—Percentage of space to be left free in a control interval for subsequent processing.

FREESPACE-%CA—Percentage of control intervals to be left free in a control area for subsequent processing.

FREESPC—Actual number of bytes of free space in the total amount of space allocated to the data or index component. Free space in partially used control intervals is not included in this statistic. Some of this space may not be accessible due to the current amount of key compression that can be performed in the index.

The remaining fields in the statistics group (except for the system timestamp field), are updated only when the data set is closed.

EXCPS—EXCP (run channel program—SVC 0) macro instructions issued by VSAM against the data or index component.

EXTENTS—Extents in the data or index component.

REC-DELETED—The number of records that have been deleted from the data or index component. Statistics for records deleted are not maintained when the data set is processed in control interval mode. For a data set that is eligible for CA_RECLAIM on a system with CA_RECLAIM enabled, this value for the index component will be the number of times CA_RECLAIM has occurred for this data set.

REC-INSERTED—For a key-sequenced data set, the number of records that have been inserted into the data component before the last record; records originally loaded and records added to the end are not included in this statistic. For relative record data sets, it is the number of records inserted into available slots; the number of records originally loaded are included in this statistic. Statistics for records inserted are not maintained when the data set is processed in control interval mode. For a data set that is eligible for CA_RECLAIM on a system with CA_RECLAIM enabled, this value for the index component will be the number of CA's that have been reused for this data set.

REC-RETRIEVED—The number of records that have been retrieved from the data or index component, whether for update or not for update. Statistics for records retrieved are not maintained when the data set is processed in control interval mode.

REC-TOTAL—The total number of records actually in the data or index component. This statistic is not maintained when the data set is processed in control interval mode. For a variable-length RRDS, this is the count of slots in the data set.

REC-UPDATED—The number of records that have been retrieved for update and rewritten. This value does not reflect those records that were deleted, but a record that is updated and then deleted is counted in the update statistics. Statistics for records updated are not maintained when the data set is processed in control interval mode.

SPLITS-CA—Control area splits. Half the data records in a control area were written into a new control area and then were deleted from the old control area. For an index component, the value reported is the number of times a split occurred when inserting a record in the next higher  level of the index above the sequence set records. For a data set that is eligible for CA_RECLAIM on a system with CA_RECLAIM enabled, the value reported here will also include the number of times that CA_RECLAIM has occurred for this data set. For a data set that is eligible for CA_RECLAIM to determine the number of CA splits that were not related to CA_RECLAIM processing take the SPLITS-CA value for the data component and subtract the value of REC-DELETED from the index component.

SPLITS-CI—Control interval splits. Half the data records in a control interval were written into a new control interval and then were deleted from the old control interval. For an index component the value reported is the number of times a split occurred when inserting a record into the    sequence set.

SYSTEM-TIMESTAMP—The time (system time-of-day clock value) the data or index component was last closed (after being opened for operations that might have changed its contents).

USER-DATA-SIZE—Displays the total length of data before compression. If the data lengths are too large to be presented in decimal, they are presented in hexadecimal format.