IBM Mainframe Forum Index
 
Log In
 
IBM Mainframe Forum Index Mainframe: Search IBM Mainframe Forum: FAQ Register
 

IEFBR14 and IDCAMS


IBM Mainframe Forums -> JCL & VSAM
Post new topic   Reply to topic
View previous topic :: View next topic  
Author Message
Ranjithkumar

New User


Joined: 10 Sep 2008
Posts: 93
Location: India

PostPosted: Thu Mar 11, 2010 3:11 pm
Reply with quote

Whats the advantage of using IDCAMS utility for deleting datasets used in a JCL, instead of BR14 ? Is it advisable to use IDCAMS instead of BR14 utility?
Back to top
View user's profile Send private message
PeterHolland

Global Moderator


Joined: 27 Oct 2009
Posts: 2481
Location: Netherlands, Amstelveen

PostPosted: Thu Mar 11, 2010 3:15 pm
Reply with quote

IEFBR14 doesnt need sysin input.
So if you dont want to use control card libraries or in stream data
IEFBR14 is the way to do it.
Back to top
View user's profile Send private message
expat

Global Moderator


Joined: 14 Mar 2007
Posts: 8797
Location: Welsh Wales

PostPosted: Thu Mar 11, 2010 3:18 pm
Reply with quote

But IEFBR14 WILL recall migrated datasets before deleting them, thus wasting time and resource.
Back to top
View user's profile Send private message
PeterHolland

Global Moderator


Joined: 27 Oct 2009
Posts: 2481
Location: Netherlands, Amstelveen

PostPosted: Thu Mar 11, 2010 3:22 pm
Reply with quote

Thats right expat.
Back to top
View user's profile Send private message
Ranjithkumar

New User


Joined: 10 Sep 2008
Posts: 93
Location: India

PostPosted: Thu Mar 11, 2010 3:29 pm
Reply with quote

Will there be any CPU savings if we used IDCAMS instead of IEFBR14? Or is it the other way around?
Back to top
View user's profile Send private message
expat

Global Moderator


Joined: 14 Mar 2007
Posts: 8797
Location: Welsh Wales

PostPosted: Thu Mar 11, 2010 3:48 pm
Reply with quote

What did you find out when you tried it for yourself ?
Back to top
View user's profile Send private message
Ranjithkumar

New User


Joined: 10 Sep 2008
Posts: 93
Location: India

PostPosted: Thu Mar 11, 2010 3:56 pm
Reply with quote

Its 00 for both utilities when i tried it out . I am not able to differentiate.
Back to top
View user's profile Send private message
expat

Global Moderator


Joined: 14 Mar 2007
Posts: 8797
Location: Welsh Wales

PostPosted: Thu Mar 11, 2010 3:59 pm
Reply with quote

Then I would guess that any difference is negligable
Back to top
View user's profile Send private message
Escapa

Senior Member


Joined: 16 Feb 2007
Posts: 1399
Location: IL, USA

PostPosted: Thu Mar 11, 2010 4:05 pm
Reply with quote

Ranjithkumar wrote:
Its 00 for both utilities when i tried it out . I am not able to differentiate.

Have you tried it for migrated dataset?
Back to top
View user's profile Send private message
Ranjithkumar

New User


Joined: 10 Sep 2008
Posts: 93
Location: India

PostPosted: Thu Mar 11, 2010 4:06 pm
Reply with quote

Thank you Expat. I read this somewhere online - "IDCAMS does not cause any tape mounts to uncatalog/delete a data set. Using IEFBR14 to uncatalog a tape data set with JCL with a DISP of DELETE causes a tape mount." Was the statement true? Does tape mounts afffect performance somehow?
Back to top
View user's profile Send private message
PeterHolland

Global Moderator


Joined: 27 Oct 2009
Posts: 2481
Location: Netherlands, Amstelveen

PostPosted: Thu Mar 11, 2010 4:17 pm
Reply with quote

With UNIT=(,,DEFER) for tapes there will be no mounting, cause
IEFBR14 doesnt do anything (like opening datasets).

To uncatalog you have to use the uncatlg parameter of the DISP statement.
Back to top
View user's profile Send private message
expat

Global Moderator


Joined: 14 Mar 2007
Posts: 8797
Location: Welsh Wales

PostPosted: Thu Mar 11, 2010 4:19 pm
Reply with quote

Ranjithkumar wrote:
IDCAMS does not cause any tape mounts to uncatalog/delete a data set. Using IEFBR14 to uncatalog a tape data set with JCL with a DISP of DELETE causes a tape mount."

What happens if you try having specified deferred mount in the JCL

Aaaaaaaah, fast fingers Peter has beaten me to that one icon_biggrin.gif

Although my testing used MOD,DELETE,DELETE with no mount.
Back to top
View user's profile Send private message
gcicchet

Senior Member


Joined: 28 Jul 2006
Posts: 1702
Location: Australia

PostPosted: Thu Mar 11, 2010 4:38 pm
Reply with quote

Hi Expat,

the mount is still issued and the the tape drive is still allocated,
,,DEFER still allocates the tape drive.


Gerry
Back to top
View user's profile Send private message
expat

Global Moderator


Joined: 14 Mar 2007
Posts: 8797
Location: Welsh Wales

PostPosted: Thu Mar 11, 2010 4:40 pm
Reply with quote

Good thinking Gerry. Thanks for the reminder icon_redface.gif
Back to top
View user's profile Send private message
parsesource

New User


Joined: 06 Feb 2006
Posts: 97

PostPosted: Thu Mar 18, 2010 12:18 am
Reply with quote

expat wrote:
But IEFBR14 WILL recall migrated datasets before deleting them, thus wasting time and resource.


if you have z/OS 1.11 and set a parm somewhere in parmlib IEFBR14 WILL NOT recall a dataset if the step-termination DISP = DELETE. the first major update for iefbr14 since 1964....
Back to top
View user's profile Send private message
dick scherrer

Moderator Emeritus


Joined: 23 Nov 2006
Posts: 19244
Location: Inside the Matrix

PostPosted: Thu Mar 18, 2010 1:47 am
Reply with quote

Hello,

Is this a change to IEFBR14 itself or a change to z/OS to recognize the situation?

Once upon a time, other than standard linkage in and out of the code, the "function" of IEFBR14 was to branch to register 14 and end as quickly as possible. . . icon_smile.gif
Back to top
View user's profile Send private message
parsesource

New User


Joined: 06 Feb 2006
Posts: 97

PostPosted: Thu Mar 18, 2010 3:33 am
Reply with quote

dick scherrer wrote:
Hello,

Is this a change to IEFBR14 itself or a change to z/OS to recognize the situation?

Once upon a time, other than standard linkage in and out of the code, the "function" of IEFBR14 was to branch to register 14 and end as quickly as possible. . . icon_smile.gif


because the recall happens before iefbr14 gets control there must be new code outside br14.
Back to top
View user's profile Send private message
dick scherrer

Moderator Emeritus


Joined: 23 Nov 2006
Posts: 19244
Location: Inside the Matrix

PostPosted: Thu Mar 18, 2010 8:47 pm
Reply with quote

Hello,

Quote:
because the recall happens before iefbr14 gets control there must be new code outside br14.
Which should mean that this is not realy an update to iefbr14?
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic View Bookmarks
All times are GMT + 6 Hours
Forum Index -> JCL & VSAM

 


Similar Topics
Topic Forum Replies
No new posts IDCAMS listcat service using cobol JCL & VSAM 1
No new posts TWS - ETT File triggering does not wo... IBM Tools 4
No new posts IDCAMS & LISTCAT with ddnames JCL & VSAM 1
No new posts Capture DSN names through SORT / IDCAMS DFSORT/ICETOOL 8
No new posts IDCAMS RENAMING VSAM FILE ALONG WITH ... JCL & VSAM 12
Search our Forums:

Back to Top