Space Parameter

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi ,

In my file the records may exceed more than 2 million. And my file length is 300 . In this case how I should define the Space parameter.

In Cylinders as well as in Tracks and Blocks

Can anyone help me for the same

Regards,
Gay251319

chandracdac · New User Joined: 15 Jun 2007 Posts: 92 Location: bangalore

Hi,
try this
This works for 3 million records also
RECORD LENTH ===> 300
//DDNAME DD DSN=YOUR.NAME,

DISK BLKS SPACE=(27900,(32259,6451),RLSE)
TRKS SPACE=(TRK,(16130,3226),RLSE)
CYL SPACE=(CYL,(1076,215),RLSE)
LRECL=300,BLKSIZE=27900
CART/TAPE LRECL=300,BLKSIZE=32700

Thanks,
Chandra

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi ,

Thanks a lot for ur reply

In this case I should use a TAPE file . Will it work fine ?

expat · Posted: Thu Oct 20, 2011 4:35 pm

Garry Carroll · Posted: Thu Oct 20, 2011 4:35 pm

Cylinders and Tracks relate to DISK, not tape. Space on TAPE depends on how long the tape is....

Garry.

expat · Posted: Thu Oct 20, 2011 4:42 pm

27900 / 300 = 93 records per half track
93 * 2 = 186 records per track

186 * 15 = 2,790 records per cylinder

3,000,000 / 2790 = 1,076 cylinders

This really is a basic question that could have, and should have, been researched before posting on a forum

Gay251319 · New User Joined: 17 Jun 2009 Posts: 57 Location: Kochi

Hi ,

Sorry . Actually mine is a TAPE file . I forget to specify that

If I am using TAPE 3490 what space I should give for the same .

Can anyone help me for the same

Regards,
Gay251319

expat · Posted: Thu Oct 20, 2011 4:43 pm

May I suggest that you read through your production JCL libraries and use exactly the same space parameters that are specified for other tape datasets.

Or a nice manual may suffice instead

dick scherrer · Posted: Thu Oct 20, 2011 7:40 pm

Hello,

At the top of the page is a link to "IBM MAnuals". You need to read the information about the SPACE parameter in the JCL Reference manual.

Hint: Pay special attention to anything about TAPE rather than DASD.

If you find something in the manual that is not clear, post what you found and your doubt. Someone here will be able to clarify.

Pete Wilson · Posted: Thu Nov 24, 2011 11:02 pm

Perhaps take note of the VOLCOUNT parameter too....

, might be relevent here.

For further reading also see the AVGREC parameter which combined with SPACE allow requests for space in units, thousands and millions of records and it calculates the trks, cyls for you. If you don't specify BLKSIZE in your JCL the system will determine the best one for you.