Portal | Manuals | References | Downloads | Info | Programs | JCLs | Mainframe wiki | Quick Ref
IBM Mainframe Computers Forums Index
 
Register
 
IBM Mainframe Computers Forums Index Mainframe: Search IBM Mainframe Forum: FAQ Memberlist Profile Log in to check your private messages Log in
 
Space parameters for a KSDS file.

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

New User


Joined: 10 Aug 2007
Posts: 30
Location: atlanta

PostPosted: Tue Aug 21, 2007 12:42 am    Post subject: Space parameters for a KSDS file.
Reply with quote

Hi All,

I need to allocate a KSDS file with alternate index. Here are the specifics. I know the record length 150 which is fixed. The index is 16 byte long and alternate index is 10 bytes long.

Now we have a limitation that maximum size of VSAM can be 4GB.

We need to determine the space parameters for the VSAM file with optimum usage of the space as we might up allocating many such files.

Can anyone please help me how best this can be done and the calculation used for determing the same.

I have gone through which detail similar stuff for flat files but wanted to know about this for VSAM.

Thanx a lot in anticipation.
Back to top
View user's profile Send private message

CICS Guy

Senior Member


Joined: 18 Jul 2007
Posts: 2150
Location: At my coffee table

PostPosted: Tue Aug 21, 2007 2:17 am    Post subject: Re: Space parameters for a KSDS file.
Reply with quote

rameshvs wrote:
We need to determine the space parameters for the VSAM file with optimum usage of the space as we might up allocating many such files.
Very short sighted, putting a person who has no idea of space requirements calculations in charge of calculating space requirements for a VSAM KSDS file and an AIX on that base cluster....
I would suggest, if you can come up with suitable interval and area sizes, that you just load the thing and see how much of the allocated spaces a set number of records occupy. Base cluster is easy, but index levels and total size is the goal.....
Back to top
View user's profile Send private message
ofer71

Global Moderator


Joined: 27 Dec 2005
Posts: 2360
Location: Israel

PostPosted: Tue Aug 21, 2007 10:53 am    Post subject:
Reply with quote

I strongly recommend to read the relevant chapter in the fine manual.

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

Global Moderator


Joined: 14 Mar 2007
Posts: 8593
Location: Back in jolly old England

PostPosted: Tue Aug 21, 2007 1:25 pm    Post subject:
Reply with quote

Is it a batch file, online file, both ?
How many records will there be ?
Going to do any inserts ?

How many duplicate AIX keys do you expect to be present, if any ?

The limit on 4GB VSAM was resolved with SMS version 1.3, about 10 years ago
Back to top
View user's profile Send private message
rameshvs
Currently Banned

New User


Joined: 10 Aug 2007
Posts: 30
Location: atlanta

PostPosted: Tue Aug 21, 2007 6:10 pm    Post subject:
Reply with quote

Thanks for all the responses.

Expat, this is a batch process. We are expecting records upto half a billion or so thats why we night end up creating more files. We will have only one AIX and there will not be any duplicates.

The 4 GB limit for VSAM I/O with C,C++ is present until z/OS V1.7 looks like got resolved with 1.8 but we are still using 1.7.
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 Execute JCL step based on the content... sprikitik JCL & VSAM 2 Tue Oct 03, 2017 10:03 am
This topic is locked: you cannot edit posts or make replies. PS file data should be passed as symb... d_sarlie JCL & VSAM 15 Tue Oct 03, 2017 5:18 am
No new posts Garbage on output file Hervey Martinez SYNCSORT 4 Wed Sep 27, 2017 12:50 am
No new posts File Aid tool to compare numeric data balaji81_k Compuware & Other Tools 2 Tue Sep 26, 2017 3:35 am
No new posts The TS7720 is out of cache space. Rex Montemayor All Other Mainframe Topics 2 Mon Sep 25, 2017 7:18 am

Facebook
Back to Top
 
Job Vacancies | Forum Rules | Bookmarks | Subscriptions | FAQ | Polls | Contact Us