What is the difference between primary and secondary
allocations for a dataset?
Answers were Sorted based on User's Feedback
Answer / guest
Secondary allocation is done when more space is required
than what has already been allocated.
Is This Answer Correct ? | 49 Yes | 6 No |
Answer / saikat dey
total storage of Space=(cyl,(5,10),rlse)is not 5 + 16*10 =
165 cylinders.
For sequential file total extent is 16 that not mean above.
Total space of it would be [(1*5)+(15*10)]=155 Cylinders.
Is This Answer Correct ? | 33 Yes | 2 No |
Answer / s
A dataset is created in extents. Extents are contiguous
space of tracks, cyls or blocks. The first extent is called
the primary allocation. As the dataset grows, dataset is
extended using secondary extents.
Is This Answer Correct ? | 25 Yes | 5 No |
Answer / sash
Primary allocation is treated as an one extend. So total
space for a dataset would be Primary + 15 * secondary.
Is This Answer Correct ? | 11 Yes | 0 No |
Answer / satya prakash
For a Dataset in primary allocation is needed. The number is
close to the total requirement as possible. The secondary
quantity is an additional quantity that can be used only if
dataset exceeds the space allocated with the primary quantity
Is This Answer Correct ? | 7 Yes | 5 No |
Answer / jignesh patel
The primary allocation is the space units given to the
empty new dataset initially. Though primary & secondary
spaces are allocated during defination it wont allow the
dataset to use the secondary allocation till the time
primary allocation fully acquired by the data of that
dataset.
As mentioned above, dataset uses the primary & secondary
spaces in the sense of EXTENT mode. the memory allocated is
virtually departed in the 16 extents. System can allocate
primary + secondary*16 space units in the best case.
Is This Answer Correct ? | 5 Yes | 14 No |
Answer / saroja kolli
Primary and the secondary allocations are the space
allocated for a particular dataset.
Primary indicates that the mian storage allcoated and for
the specified dataset the storage allocated primarily is
not sufficient then it will go for the secondary extents.
Secondary allocation will be usually 16 extents
Example:
Space=(cyl(5,10),rlse) is specified for any dataset then
the dataset will be allocated with the total storage of
5 + 16*10 = 165 cylinders.
Is This Answer Correct ? | 16 Yes | 29 No |
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