I'm not entirely sure I understand your question but I'll try to explain
how DFSORT uses Hiperspace and maybe that will help.
As part of DFSORT initialization, the characteristics of the sort are
evaluated along with available resources and a decision is made about what
type and how much storage to use.
If a decision was made to use Hiperspace storage than a Hiperspace is
created. At this point the Hiperspace is empty which may be why you see it
as "swapped out".
As the DB2 utility passes input records to DFSORT, they are written to the
Hiperspace. I'm guessing this filling of the Hiperspace might be what is
looking like page ins to you.
Once all input records have been processed, DFSORT then begins to read the
records back from the Hiperspace and pass them back to the DB2 Utility in
sequence. Normally we use RELEASE=YES so that the pages are released as
they are read.
At completion, DFSORT then deletes the Hiperspace.
Have a nice day,
Dave Betten
DFSORT Development, Performance Lead
IBM Corporation
email: bet...@us.ibm.com
1-301-556-0943
DFSORT/MVSontheweb at http://www.ibm.com/storage/dfsort/
IBM Mainframe Discussion List wrote on 01/23/2009
01:32:12 PM:
> We are trying to understand how hiperspace is being used. z/os 1.9.
Using
> DSNUTILB and it's invocation of df/sort, it appears that when the
hiperspace
> is initially created, it is immediately swapped out, then demand paged
back
> in. When I look at type30 records, or in MON3 we see pagins, but never
any
> page outs, nor any swap outs during the step duration. in MON3, we see
> sometimes 1K's worth of pages in DIV status, but again, we never see any
> page/swap outs. What am I missing or where should I be looking ?
>
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