Calculating the Number of Cylinders/Tracks - Finalist - 10.0

Finalist Installation

Product type
Software
Portfolio
Verify
Product family
Data Quality - Postals
Product
Finalist
Version
10.0
Language
English
Product name
Finalist
Title
Finalist Installation
Copyright
2023
First publish date
1984
Last updated
2024-05-15
Published on
2024-05-15T00:57:53.836782

This section provides instructions for calculating the number of cylinders/tracks required for a given Finalist VSAM cluster. The number of cylinders/tracks required varies according to type of DASD, record size, and control interval size. The actual number of records in the Finalist VSAM clusters also varies slightly with each new update or distribution. Refer to the IBM VSAM Administration Guide to find capacity and physical record sizes by device type.

The Technical Bulletin, available on the Precisely website, shows the record counts for each of the files. Use the information from the Technical Bulletin and the following formula to calculate the number of cylinders/tracks that a given VSAM cluster requires.

  1. Subtract 8 from the control interval size of the file. Divide this value by the record size (LRECL). The result is the number of logical records per VSAM physical record.
  2. Multiply the result from step 1 by the number of physical records that fit on one track. The chart in the IBM VSAM Administration Guide (z/OS users) shows the number of physical records that fit on one track. The result is the total number of VSAM physical records in the file.
  3. Divide the total number of records in the file by the result from step 2. The result is the number of tracks required for the file. To find the number of cylinders required, divide the number of tracks required by the number of tracks per cylinder.

This sample calculation demonstrates how to calculate the number of cylinders/tracks for a 17,479 record VSAM cluster having a record size of 4088 and a control interval size of 4096 on 3390 DASD.

1.   4096  (VSAM control interval size)
  -     8  (VSAM overhead)
     4088  (Number of data bytes per physical record)
  /  4088  (Divide by record size)
        1  (Number of logical records per physical record)

2.      1  (Number of logical records per physical record)
  X    12  (Physical records per track for 3390 DASD)
       12  (Number of logical records per track for 3390 DASD)

3.  17479  (Total number of records in the file)
  /    12  (Number of logical records per track for 3390 DASD)
     1457  (Total number of 3390 tracks required)
  /    15  (Tracks per cylinder for 3390)
       98  (Number of cylinders required)