ABCs of z/OS System Programming Volume 3 - IBM Redbooks

Chapter 3. Extended access volumes
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z/OS V1R10 introduced extended address volume (EAV), which allowed DASD storage
volumes to be larger than 65,520 cylinders. The space above the first 65,520 cylinders is
referred to as cylinder-managed space. Tracks in cylinder-managed space use extended
addressing space (EAS) techniques to access these tracks. Data sets that can use
cylinder-managed space are referred to as being EAS-eligible.
With z/OS V1R10, only VSAM data sets are EAS-eligible. You can control whether VSAM
data sets can reside in cylinder-managed space by including or excluding EAVs in particular
storage groups. For non-SMS managed data sets, control the allocation to a volume by
specifying a specific VOLSER or esoteric name.
With z/OS V1R11, extended-format sequential data sets are now EAS-eligible. You can
control whether the allocation of EAS-eligible data sets can reside in cylinder-managed space
using both the methods supported in z/OS V1R10 and by using the new EATTR data set
attribute keyword.
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