Portal | Manuals | References | Downloads | Info | Programs | JCLs | Master the Mainframes
IBM Mainframe Computers Forums Index
 
Register
 
IBM Mainframe Computers Forums Index Mainframe: Search IBM Mainframe Forum: FAQ Memberlist Usergroups Profile Log in to check your private messages Log in
 

 

SIze of Tape DSN

 
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> JCL & VSAM
View previous topic :: :: View next topic  
Author Message
rahulbank

New User


Joined: 25 Sep 2008
Posts: 66
Location: Bengaluruuuuuu

PostPosted: Sat Apr 25, 2009 12:33 am    Post subject: SIze of Tape DSN
Reply with quote

Hi,

Is there a way to find out the size of a Dsn in terms of either tracks or bytes which resides on a TAPE(and this is not an HSM tape).
Back to top
View user's profile Send private message

Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 8121
Location: East Dubuque, Illinois, USA

PostPosted: Sat Apr 25, 2009 12:53 am    Post subject:
Reply with quote

If you know the number of blocks on the tape and the block size, you can compute it easily enough. What information do you have about the tape?
Back to top
View user's profile Send private message
rahulbank

New User


Joined: 25 Sep 2008
Posts: 66
Location: Bengaluruuuuuu

PostPosted: Sat Apr 25, 2009 1:12 am    Post subject:
Reply with quote

I know the number of blocks the dsn has on the tape by viewing the job log in sar and the block size too of the tape....
Back to top
View user's profile Send private message
Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 8121
Location: East Dubuque, Illinois, USA

PostPosted: Sat Apr 25, 2009 1:19 am    Post subject:
Reply with quote

Multiply block size times number of blocks to get bytes in file. Use the usual formula to convert bytes into tracks or cylinders. And be aware the counts may be a little different if the file is variable instead of fixed length records.
Back to top
View user's profile Send private message
Terry Heinze

JCL Moderator


Joined: 14 Jul 2008
Posts: 1249
Location: Richfield, MN, USA

PostPosted: Sat Apr 25, 2009 6:23 am    Post subject:
Reply with quote

...and even for an FB file, the last block may not be a full block.
Back to top
View user's profile Send private message
rahulbank

New User


Joined: 25 Sep 2008
Posts: 66
Location: Bengaluruuuuuu

PostPosted: Tue Apr 28, 2009 7:03 pm    Post subject:
Reply with quote

Thanks for the answer I had this question in my mind for along time...Two more things...

Do you know how to convert the tracks to blocks.
Also in case the file is variable is there a way to calculate the same tape DSN.
Back to top
View user's profile Send private message
Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 8121
Location: East Dubuque, Illinois, USA

PostPosted: Tue Apr 28, 2009 7:15 pm    Post subject:
Reply with quote

I'm not 100% sure I understand what you mean by "convert the tracks to blocks". Your original question was about a tape -- which has no tracks to convert. A 3390 track is blocked typically around half track blocking which is 27998 bytes, although any block size can be used.

A variable length file is much harder to calculate. For example, if the program writing the records is COBOL, the AWO compiler option affects the file. If you have SYNCSORT installed at your site, the HISTOGRM variable record analyzer will give you the numbers to make your calculation. There may be an equivalent DFSORT utility but I've never looked for one so you'd have to ask on the DFSORT forum.
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> JCL & VSAM All times are GMT + 6 Hours
Page 1 of 1

 

Search our Forum:

Similar Topics
Topic Author Forum Replies Posted
No new posts To find out size allocated to a seque... ashek15 JCL & VSAM 15 Thu Apr 27, 2017 9:42 am
No new posts Length of Tape file Mohan Kothakota JCL & VSAM 9 Thu Apr 20, 2017 10:24 pm
No new posts TAPE VERIFY utility?? MrExtraordinare JCL & VSAM 3 Fri Dec 09, 2016 10:57 pm
No new posts Increase the screen size after split mistah kurtz TSO/ISPF 2 Fri Sep 02, 2016 6:39 pm
No new posts stacking files on a tape Pedro JCL & VSAM 7 Wed Aug 17, 2016 11:11 pm


Facebook
Back to Top
 
Mainframe Wiki | Forum Rules | Bookmarks | Subscriptions | FAQ | Tutorials | Contact Us