I am creating a VSAM dataset with some standard template. In the Define command we are specifying space in terms if RECORDS. Can anyone tell me how to calculate the No of tracks and cylinders from the Records?
Joined: 06 Jun 2008 Posts: 8217 Location: Dubuque, Iowa, USA
From the DFSMS AMS for Catalogs manual:
If you select RECORDS, the amount of space allocated is the minimum number of tracks that are required to contain the given number of records. The maximum number of records is 16,777,215. If RECORDS is specified for a linear data set, space is allocated with the number of control intervals equal to the number of records.
At a high level: tracks = #records divided by (#records per CI times #CI per track), assuming ESDS or KSDS and not accounting for KSDS index. The CI size is critical to know how much space is being used.
Joined: 14 Mar 2007 Posts: 8631 Location: Back in jolly old England
Mmmmmmmmmm, not sure if this one still holds true, but once upon a time in a galaxy far far away, if you used RECORDS as the allocation parameter then FSPC was ignored in a cluster definition if specified.