Performance Issue



JES, JES2, JCL utilities, IDCAMS, Compile & Run JCLs, PROCs etc...

Performance Issue

Postby gali prasad » Thu Jul 15, 2010 7:54 pm

Dear all,

My application has below SORT utility in JCL and basically SORT is used here to copy large data from large VSAM file to a flat file as a backup purpose

//S010 EXEC PGM=SORT
//SORTIN DD DSN=Large vsam file,DISP=SHR,
// AMP=(AMORG,'BUFND=20')
//SORTOUT DD DSN=flat file,
// DISP=(NEW,CATLG,DELETE),
// UNIT=CART,LABEL=EXPDT=99000,VOL=(,,,99),
// DCB=PRD.T.LRECL150
//*
//SYSIN DD DSN
SORT FIELDS=COPY

Above process is nearly taking more time to run and please suggest me if any improvements can be done or else any utility that can replace above.

Thankyou very much,
Prasadg
gali prasad
 
Posts: 10
Joined: Wed Jul 14, 2010 6:01 pm
Has thanked: 0 time
Been thanked: 0 time

Re: Performance Issue

 

Re: Performance Issue

Postby NicC » Thu Jul 15, 2010 10:43 pm

IDCAMS REPRO - it was invented for working with VSAM files
ADRDSSU - it was invented for taking backups
The problem I have is that people can explain things quickly but I can only comprehend slowly.
Regards
Nic
NicC
Global moderator
 
Posts: 2692
Joined: Sun Jul 04, 2010 12:13 am
Location: Pushing up the daisys (almost)
Has thanked: 4 times
Been thanked: 105 times

Re: Performance Issue

Postby Robert Sample » Thu Jul 15, 2010 11:57 pm

Why do people have trouble providing necessary details? For example, we back up 2 VSAM files totaling 37,000 cylinders (11 mod 3 disk packs or about 30 gigabytes) in 43 minutes using ADRDSSU -- going to tape. That gives you size and time values for comparison purposes -- details that are needed by responders!

How big is a "large" VSAM file to you? How much time is the SORT step taking?
Robert Sample
Global moderator
 
Posts: 3367
Joined: Sat Dec 19, 2009 8:32 pm
Location: Dubuque, Iowa, USA
Has thanked: 1 time
Been thanked: 222 times

Re: Performance Issue

Postby gali prasad » Fri Jul 16, 2010 11:35 am

Hello Robert,

I will check jobs and will let you know information.

Thanks for your response.
gali prasad
 
Posts: 10
Joined: Wed Jul 14, 2010 6:01 pm
Has thanked: 0 time
Been thanked: 0 time

Re: Performance Issue

Postby Bill Dennis » Sat Jul 17, 2010 12:42 am

Also, are the output tapes real or virtual? What media type? 3490, 3590, 3592?
Regards,

Bill Dennis

Disclaimer: My comments on this forum are my own and do not represent the opinions or suggestions of any other person or business entity.
Bill Dennis
 
Posts: 278
Joined: Thu May 15, 2008 9:45 pm
Has thanked: 0 time
Been thanked: 0 time

Re: Performance Issue

Postby gali prasad » Mon Jul 19, 2010 11:23 am

Dear Robert,

The VSAM file has around 3240860 records and its consuming time of nearly one minute.

Please let me know if any advice.

Thankyou.
gali prasad
 
Posts: 10
Joined: Wed Jul 14, 2010 6:01 pm
Has thanked: 0 time
Been thanked: 0 time

Re: Performance Issue

Postby dick scherrer » Mon Jul 19, 2010 12:55 pm

Hello,

Why do you believe 1 minute is too much?
Hope this helps,
d.sch.
User avatar
dick scherrer
Global moderator
 
Posts: 6304
Joined: Sat Jun 09, 2007 8:58 am
Has thanked: 3 times
Been thanked: 91 times

Re: Performance Issue

Postby gali prasad » Mon Jul 19, 2010 2:36 pm

Dear Dick,

The job runs nearly for 2 minutes in some cases, based on size of file and I want to know if there is any suggestion that can improve my performance if my input VSAM file crosses 100 millions.

Hope you understand my issue.

Thankyou very much,
gali prasad
 
Posts: 10
Joined: Wed Jul 14, 2010 6:01 pm
Has thanked: 0 time
Been thanked: 0 time

Re: Performance Issue

Postby NicC » Mon Jul 19, 2010 3:33 pm

2 MINUTES! For 3 MILLION records? I would start thinking about other methods if it approaches 30-45 minutes. You will be retired by then!
The problem I have is that people can explain things quickly but I can only comprehend slowly.
Regards
Nic
NicC
Global moderator
 
Posts: 2692
Joined: Sun Jul 04, 2010 12:13 am
Location: Pushing up the daisys (almost)
Has thanked: 4 times
Been thanked: 105 times

Re: Performance Issue

Postby Robert Sample » Mon Jul 19, 2010 5:06 pm

Please tell me you are kidding us about being worried about performance. If you are backing up 100 million records, one hour elapsed time is not by any means unusual or out of line. If you want to reduce this time, you will have to work with your site support group to schedule the job to run when the system workload is at a minimum; nothing else will help you.
Robert Sample
Global moderator
 
Posts: 3367
Joined: Sat Dec 19, 2009 8:32 pm
Location: Dubuque, Iowa, USA
Has thanked: 1 time
Been thanked: 222 times


Return to JCL

 


  • Related topics
    Replies
    Views
    Last post