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
 

 

Maximum Number of Records can be saved on Dasd

 
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> JCL & VSAM
View previous topic :: :: View next topic  
Author Message
aryanpa1

New User


Joined: 26 May 2007
Posts: 45
Location: Chennai

PostPosted: Thu May 07, 2009 10:16 pm    Post subject: Maximum Number of Records can be saved on Dasd
Reply with quote

Hi Team,

One of my new job is creating Millions of records in a single DASD file.I want to know what is the maximum no. of records I can place in this file. The count may go to 50 millions sometimes.

Record length is 300 bytes.

Can you please let me know the maximum no. of records I can store in this and the process how I can calculate this.

Thank you,
Pavan
Back to top
View user's profile Send private message

dick scherrer

Site Director


Joined: 23 Nov 2006
Posts: 19270
Location: Inside the Matrix

PostPosted: Thu May 07, 2009 10:21 pm    Post subject:
Reply with quote

Hello,

Suggest you create a file with 5 million records using the recfm and blksize your "real" file will use. Then all you need to do is multiply.

One of my transaction files has around 8 million records that are 1052 bytes long and this file typically requires about 1 3390 volume.

If you search in the forum, there have been a few topics on space calculation.

I suspect that the largest possible file would be far more than you could afford to process. . .
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: Thu May 07, 2009 10:24 pm    Post subject:
Reply with quote

Take a look at SPACE parameter in a JCL
Back to top
View user's profile Send private message
aryanpa1

New User


Joined: 26 May 2007
Posts: 45
Location: Chennai

PostPosted: Thu May 07, 2009 10:36 pm    Post subject:
Reply with quote

Quote:
I suspect that the largest possible file would be far more than you could afford to process. . .

Thanks Dick, Is 50 million records file can be processed easily
Back to top
View user's profile Send private message
Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 7931
Location: Bellevue, IA

PostPosted: Thu May 07, 2009 10:46 pm    Post subject:
Reply with quote

If I did the math correctly, and you're not running large or extended sequential files under z/OS 1.10, you can fit about 719 million 300-byte records on a z?OS system.

Quote:
Is 50 million records file can be processed easily
another of those questions that can be answered
Yes, no, maybe
because it depends -- what do you consider "easily"? Has the JCL been optimized for buffers? Are there any constraints on the processing (for example, it is a daily process and you discover it's taking 32 hours)?
Back to top
View user's profile Send private message
aryanpa1

New User


Joined: 26 May 2007
Posts: 45
Location: Chennai

PostPosted: Thu May 07, 2009 10:52 pm    Post subject:
Reply with quote

"Easily" in my sense , the time it is going to take for simple read of the file.
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: Thu May 07, 2009 10:58 pm    Post subject:
Reply with quote

Robert Sample wrote:
z?OS system.
Typo or subtle hint?
Back to top
View user's profile Send private message
Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 7931
Location: Bellevue, IA

PostPosted: Thu May 07, 2009 10:58 pm    Post subject:
Reply with quote

Flat file, sequential read -- easy enough. How long (in elapsed time) it's going to take will depend upon the site. Factors that have a bearing include (but are not limited to) Workload Manager policy, number of active address spaces in the system, channel contention, disk contention, I/O speed, CPU speed, program processing, buffering, block size. The only way to know for sure is going to be run a significant test (say 10-100% of the file) during the normal expected window.
Back to top
View user's profile Send private message
Robert Sample

Global Moderator


Joined: 06 Jun 2008
Posts: 7931
Location: Bellevue, IA

PostPosted: Thu May 07, 2009 11:02 pm    Post subject:
Reply with quote

CICS guy ... typo, definitely typo. Sigh. Although subtle hint could work, too. Now, back to the LPAR I toasted this morning to see if it can be recovered or if it's time to restore from backup ...
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 Removing Duplicates based on certain ... chandracdac DFSORT/ICETOOL 8 Fri Dec 09, 2016 4:40 am
No new posts Limit duplicate records in the SORT pshongal SYNCSORT 6 Mon Nov 21, 2016 12:54 pm
No new posts How to split the records using the am... vnktrrd DFSORT/ICETOOL 24 Fri Oct 28, 2016 7:33 pm
No new posts Sort records based on numeric field. Alks SYNCSORT 2 Wed Oct 19, 2016 10:14 pm
No new posts abend sort based on count records in ... anatol DFSORT/ICETOOL 5 Mon Oct 17, 2016 10:10 pm


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