IBM Mainframe Forum

Trying to understand why all the VSAM KSDS files at my installation have the number of CI's per CA on the Index component on track boundries. Is this something that is a VSAM limitation or is it something (site dependent) that's doing it to us? For example, one particular file has 8192 Data componet (and Ci/CA of 90), and 4096 Index component where the CI/CA is 12. Both Data and INdex IDCAMS allocations are in Cylinders and I'm confused why 'something' is preventing Cylinder boundries on CI's per CA for Index component.

You say that the SPACE allocation for both is done with CYLINDERS.

What happens when you define a cluster using CYLINDERS in the CLUSTER section of the define. The Index gets allocated in tracks.

To force the INDEX portion to be allocated in CYLINDERS, you need to specify the space allocations in the component levels of the define cluster, not at the cluster level.

The CI/CA value for the index is not important as it is for the data.