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 | | From: | Glen Gunselman | | Subject: | Re: calling all VSAM experts... | | Date: | 21 Jan 2005 10:11:13 -0800 |
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 | Bob,
I haven't set up managed-SAM defines in decades but VSE/VSAM V6R4
User's Guide and Application Programming (section 4.6.6) figure 25
indicates that NOREUSE is possible.
________________________________________________________________________________________
| Figure 25. Modeling of DEFINE Parameters
|
|_____________________ ___________________ _________
____________________________________|
snip ...
|_____________________|_________|_________|_________|____________________________________|
| REUSE | Yes | Yes | Yes | NOREUSE is the
default. |
|_____________________|_________|_________|_________|____________________________________|
.... snip
Glen Gunselman
>>> RJacobson@decare.com 1/21/2005 9:28:27 AM >>>
For a VSAM file to have more than 16 extents per volume it must be
defined
NOREUSE. When managed-SAM files are defined implicitly, they are
defined
REUSE, so they are subject to the 16 extent per volume limit.
Therefore,
your only chance to have a managed-SAM file with more than 16 extents
per
volume is to define it explicitly.
Bob Jacobson
(651) 994-5329
rjacobson@decare.com
Michael Rosinger
com>
To
Sent by: "VSE Discussion List"
owner-vse-l@Lehig
h.EDU
cc
Subject
01/21/2005 09:05 Re: calling all VSAM experts...
AM
Please respond to
vse-l@Lehigh.EDU
Glen,
Yes, that must be what they are referring to. Can you tell me if this
applies to VSAM-managed SAM?
We use a whole lot of *implicitly* defined VSAM/SAM for transient data
files. We never get more than 16 extents per volume in the catalog.
From
what I can tell in the books, to take advantage of the 123 extents the
dataset has to be defined REUSE and it seems to hint that it must be
defined *explicitly*. If that's the case, that would explain why we
never
see more than 16 extents per volume. What do you think?
Glen Gunselman wrote:
> Michael,
>
> The number you are looking for is 123 not 128. Search the VSE/VSAM
> Commands manual for 123 and you will find the details.
>
--
Michael Rosinger
Systems Programmer/DBA
Computer Credit, Inc.
640 W. 4th Street
Winston-Salem, NC 27101
voice : 336-761-1524
fax : 336-761-8852
email : mrosinger at cciws dot com
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| | From: | RJacobson at decare.com | | Subject: | Re: calling all VSAM experts... | | Date: | 21 Jan 2005 11:44:54 -0800 |
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I created a sample managed-SAM file in VSESPUC using the following
definition.
DEFINE CLUSTER (NAME(DNPROD.SORTIN.AGEMEM) -
CISZ(512) -
NONINDEXED -
RECORDFORMAT(FB(80)) -
SPEED -
NOREUSE -
VOLUMES(DOSRES) -
TRK (1 1) -
RECORDSIZE(160 160) -
SHAREOPTIONS(2 3)) -
DATA (NAME('DNPROD.SORTIN.AGEMEM.DATA'))
VSAM accepted the definition. I then loaded 9999 card images into the file
with REPRO. According to my calculations, 1 track with a 512 byte CI size
should only hold about 294 records, so 9999 records should require 35
extents. A LISTCAT of the file after the load showed exactly that.
REPRO INFILE(SYSIPT) -
OUTFILE(DISKOUT -
ENV(RECORDSIZE(80) -
BLOCKSIZE(160) -
RECFM(FB) -
) -
)
Bob Jacobson
(651) 994-5329
rjacobson@decare.com
"Glen Gunselman"
.edu> To
Sent by: "VSE Discussion List"
owner-vse-l@Lehig
h.EDU cc
Subject
01/21/2005 12:10 Re: calling all VSAM experts...
PM
Please respond to
vse-l@Lehigh.EDU
Bob,
I haven't set up managed-SAM defines in decades but VSE/VSAM V6R4
User's Guide and Application Programming (section 4.6.6) figure 25
indicates that NOREUSE is possible.
________________________________________________________________________________________
| Figure 25. Modeling of DEFINE Parameters
|
|_____________________ ___________________ _________
____________________________________|
snip ...
|_____________________|_________|_________|_________|____________________________________|
| REUSE | Yes | Yes | Yes | NOREUSE is the
default. |
|_____________________|_________|_________|_________|____________________________________|
.... snip
Glen Gunselman
>>> RJacobson@decare.com 1/21/2005 9:28:27 AM >>>
For a VSAM file to have more than 16 extents per volume it must be
defined
NOREUSE. When managed-SAM files are defined implicitly, they are
defined
REUSE, so they are subject to the 16 extent per volume limit.
Therefore,
your only chance to have a managed-SAM file with more than 16 extents
per
volume is to define it explicitly.
Bob Jacobson
(651) 994-5329
rjacobson@decare.com
Michael Rosinger
com>
To
Sent by: "VSE Discussion List"
owner-vse-l@Lehig
h.EDU
cc
Subject
01/21/2005 09:05 Re: calling all VSAM experts...
AM
Please respond to
vse-l@Lehigh.EDU
Glen,
Yes, that must be what they are referring to. Can you tell me if this
applies to VSAM-managed SAM?
We use a whole lot of *implicitly* defined VSAM/SAM for transient data
files. We never get more than 16 extents per volume in the catalog.
From
what I can tell in the books, to take advantage of the 123 extents the
dataset has to be defined REUSE and it seems to hint that it must be
defined *explicitly*. If that's the case, that would explain why we
never
see more than 16 extents per volume. What do you think?
Glen Gunselman wrote:
> Michael,
>
> The number you are looking for is 123 not 128. Search the VSE/VSAM
> Commands manual for 123 and you will find the details.
>
--
Michael Rosinger
Systems Programmer/DBA
Computer Credit, Inc.
640 W. 4th Street
Winston-Salem, NC 27101
voice : 336-761-1524
fax : 336-761-8852
email : mrosinger at cciws dot com
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