IBM Mainframe Forum

Hi All,

In our application environment, we run jobs to load batch VSAM KSDS file to VSAM Online via SYNCSORT copy (SORT FIELDS=COPY).

The volume of data is huge.

In this case, the data count in the file is around 19Million records and it's variable record length with 1000 bytes minimum and maximum 7500 bytes.

It's taking around 35mins to load the data from one vsam to another. We are trying to see if we can do any fine tuning, to improve the performance, your guidance will be more helpful.

I did run test jobs to see if there is any difference when i use ICEGENER instead of using PGM=SORT, it did give me slight improvement by reducing the elapsed time to 30mins, is there any parameters that I should use to boost the performance further to reduce the elapsed time ?

ICEGENER Step:

//STEPX EXEC PGM=ICEGENER
//SYSPRINT DD SYSOUT=*
//SYSUT1 DD DSN=INPUT.FILE,DISP=SHR
//SYSUT2 DD DSN=OUTPUT.FILE,DISP=SHR
//SYSIN DD DUMMY

SORT Step:

//SORT1 EXEC PGM=SORT (invoking SYNCSORT FOR Z/OS 2.1.1.1R)
//SORTIN DD DSN=INPUT.FILE,DISP=SHR
//SORTOUT DD DSN=OUTPUT.FILE,DISP=SHR
//SYSIN DD *
SORT FIELDS=COPY
//*

Hello,

How about IDCAMS, coupled with ample BUF* coded in the JCL? If it is just a dump of data from x to y, I feel IDCAMS would be relatively quicker.
How about also looking at the CISIZE definition of the KSDS?

If the file is accessed sequentially for most of the activties, you can look at increaing CISIZE to a larger number (than the RECL).
Though, would highly recommend You test it out to come up with an optimized value per your site; an incomplete/incorrect analysis with parameters can land you a mess in long run, especially if CICS environment is involved.

Talk to your sysprogs as well, for their recommendations.

Yes, as long as your z/OS is fairly up-to-date, you will probably get better performance to load/unload a KSDS using IDCAMS REPRO.

Your ICEGENER and SORT steps will basically produce identical results to each other. Have a look at the output from the two steps. Elapsed times can easily vary, depending on "machine load".

IDCAMS should be better. Aki88 has made some useful points.

It would be a good idea to talk formally to your technical/operations support. They may have suggestions which depend on the actual relative importance of your jobs (they may be very important to you, but less important overall within the schedule).