What is the historical database?
A unique historical database exists for each PAS. As data is gathered by a PAS's data collectors, the historical recorder writes data to the PAS's historical database. One set of records is written by the historical recorder at the end of each interval.
With MainView for z/OS version 2.7.00 or later, the PAS can optionally have a second historical recorder and database that are used to record long-term history. For more information about long-term data collection, see .
The historical database consists of the following logical components:
Up to 100 data sets (VSAM clusters), to house data from the recent past and, optionally, to serve as a receptacle for data that has been loaded from archived data.
Each data set is either:
Allocated to the PAS by a HISTDSnn DD statement in the PAS started task procedure
Dynamically allocated with the DSLIST view
For long-term history data sets, the DD statement is HST1DSnn. To access the DSLIST view for long-term history, first use the DSLISTZ view to display information about both historical databases, and then hyperlink to the appropriate DSLIST view.
An optional archive, consisting of a tape library or offline data sets, to store data that is too outdated or voluminous to maintain online
MainView provides the tools to allocate and maintain historical data sets.