I apologize to all. The Correct JCL is below. It must use INFILE
of DD DUMMY.
IDCAMS TO ALLOCATE EMPTY FILE VS USING IEFBR14 AS BR14 DOES NOT USE
SDB or RLSE SPACE
//STEP010 EXEC PGM=IDCAMS
//DD1 DD DUMMY CAN USE DD DUMMY OR DD * WITH NO DATA
//DD2 DD DSN=GRT.GIOIDXM.TEST.BLK1(+1),
// DISP=(NEW,CATLG,DELETE),
// DCB=(BLKSIZE=0,DSORG=PS,LRECL=80,RECFM=FB),
// SPACE=(CYL,(100,200),RLSE),UNIT=DISK
//DD3 DD DSN=GRT.GIOIDXM.TEST.BLK2,
// DISP=(NEW,CATLG,DELETE),
// DCB=(BLKSIZE=0,DSORG=PS,LRECL=80,RECFM=FB),
// SPACE=(TRK,(180,180),RLSE),UNIT=DISK
//SYSPRINT DD SYSOUT=*
//SYSIN DD *
REPRO INFILE(DD1) OUTFILE(DD2)
REPRO INFILE(DD1) OUTFILE(DD3)
/*
-----Original Message-----
From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On
Behalf Of David Spiegel
Sent: Wednesday, May 11, 2022 1:36 PM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject: Re: Potential Resource Savings Techniques
Hi Dave,
I looked at my Data Class definitions and saw nothing related to
writing an EOF.
Maybe you have an Exit or Storage Management product (e.g. CA Disk,
Mainview SRM).
Regards,
David
On 2022-05-11 13:27, Gibney, Dave wrote:
> I may be mistaken about the RLSE or perhaps it is a function of
my default DATACLAS. I know the EOF is there.
>
>> -----Original Message-----
>> From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On
>> Behalf Of David Spiegel
>> Sent: Wednesday, May 11, 2022 10:23 AM
>> To: IBM-MAIN@LISTSERV.UA.EDU
>> Subject: Re: Potential Resource Savings Techniques
>>
>> Hi Dave,
>> I tested it. Your hypothesis is false (i.e. RLSE is not done.)
>>
>> Regards,
>> David
>>
>> On 2022-05-11 13:12, Gibney, Dave wrote:
>>> If SMS-managed and DSORG known, an unopened new allocation will have
>> an EOF set and RLSE will be process.
>>>> -----Original Message-----
>>>> From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On
>>>> Behalf Of David Spiegel
>>>> Sent: Wednesday, May 11, 2022 9:20 AM
>>>> To: IBM-MAIN@LISTSERV.UA.EDU
>>>> Subject: Re: Potential Resource Savings Techniques
>>>>
>>>> Hi Paul,
>>>> Allocation does allocation and nothing but allocation.
>>>> It does not write anything at all.
>>>>
>>>> Regards,
>>>> David
>>>>
>>>> On 2022-05-11 12:17, Paul Gilmartin wrote:
>>>>> On Wed, 11 May 2022 15:53:20 +0000, Farley, Peter x23353 wrote:
>>>>>
>>>>>> Only if your SYSIN is not DUMMY. When SYSIN for IDCAMS is DUMMY
>> it
>>>> does (and can do) nothing at all, rather more expensively in CPU
>>>> time
>> than
>>>> IEFBR14, but still nothing by comparison.
>>>>>> Only if you are allocating and using REPRO from a DUMMY to a new
>>>> sequential file or an actual DEFINE for a VSAM cluster for instance
>>>> would IDCAMS do what you describe.
>>>>> Will it not write an end-of-file at the first extent and RLSE all
>>>>> but the first allocation unit of SPACE?
>>>>>
>>>>> (I suspect the OP did not intend his use of "SYSIN".)
>>>>>
>>>>> In the Bad Old pre-SMS Days, I sometimes relied on a primary
>>>>> allocation of 0 to preclude subsequently reading residual data.
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: <David> <Mingee>
>>>>>> Sent: Wednesday, May 11, 2022 11:46 AM
>>>>>>
>>>>>> IDCAMS does an open and close on the new file and writes zero
>> records,
>>>> so if RLSE is coded with the SPACE for output file(s) then the
>>>> unused trks
>> or
>>>> cyls
>>>>>> Are released. Secondary space will be used if needed when data
>>>>>> is
>>>> created in the file later.
>>>>>> -----Original Message-----
>>>>>> From: David Spiegel
>>>>>> Sent: Wednesday, May 11, 2022 11:07 AM
>>>>>>
>>>>>> I do not understand this at all.
>>>>>> How does any program differ from IEFBR14 (with respect to
>>>> allocation/freeing unused disk space by DD Statement)?
>>>>>> Maybe your shop has an Exit or add-on product which does Storage
>>>> Management?
>>>>>> On 2022-05-11 01:53, <David> <Minge > wrote:
>>>>>>> 5. Consider changing IEFBR14 for allocating new files to IDCAMS
>> with
>>>>>>> SYSIN DD DUMMY. This will release unused disk space.
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