A striped VSAM data set can have 255 extents per stripe in the data component. Only the data component is striped. The index component of a striped VSAM data set has a limit of 255 extents, regardless of striping. Because a striped VSAM data set can have a maximum of 16 stripes, a striped data component can have a maximum of 4080 extents.

Starting in z/OS V1R7, the 255-extent per stripe limit is removed if the extent constraint removal parameter in the data class is set to Y (yes). The default value is N (no), to enforce the 255-extent limit. This limit must be enforced if the data set might be shared with a pre-V1R7 system.