2. Planning for Installation and Use of CA MICS › 2.3 Installation Planning and Parameter Specification › 2.3.4 Database Space Modeling Facility

2.3.4 Database Space Modeling Facility

A Database Space Modeling Facility is provided to help
estimate the amount of DASD space required for a new
database.  This process takes as input data from about one
day and runs a DAILY job with a temporary database. This
temporary database is analyzed together with the online data
retention requirements defined to determine the required DASD
space (in tracks) for allocating the entire CA MICS database.
Three reports are produced quantifying the database space
requirements.  They are the Database Space Estimator Libname
Summary, Information Area Summary, and File Summary reports.

Note that this process is only an approximation. You can
allocate your database files with large secondary allocations
and begin running database updates.  Later you can refine
your space allocations based on actual space usage.

The steps involved in estimating the database space
requirements include:

    1.  Collect the required input data using the
        Installation Preparation Worksheets.  Complete the
        Data Retention worksheets for each product in the
        unit.

    2.  Using the worksheets, modify the prefix.MICS.PARMS
        DBMODEL member.

    3.  Execute the Database Space Modeling Facility to
        produce the space analysis reports.

    4.  Evaluate the results and either modify the inputs
        and redo step 3 or, if satisfied, continue to step 5.

    5.  Execute the Database Generation Facility in order to
        implement the database definition (SAS MACRO
        generation).

Steps 2 through 5 will normally be performed during
installation, but the details are included here so that the
entire estimation process can be understood more readily.

Note that when changes are made to database retention
definitions, the CYCLEGEN job must be executed in order to
generate database cycles according to the new definitions.

The following sections explain database space modeling more
fully.

    1 - Preparing the Modeling Input
    2 - Executing the Database Space Modeling Facility
    3 - Analyzing DASD Space Estimates