Parallel Processing in Batch

[cris_anderson]

Hi All,

   I'm looking for clarification on a possible issue with using Parallel Processing in Batch Jobs.   We have discovered we have 4 Different Batch Jobs that are all executing a Single Step that uses Parallel Processing and all 4 of these Batch Jobs start at the same time.   The parallel processor on all for of these jobs is the same.

  What I'm trying to confirm is the impact of running 4 programs at the same time all using parallel processing and the same parallel processing group.   Logically this appears to be a bad practice but wanted to confirm with the experts as I believe this will cause all available work processes to be consumed based on the configuration of the parallel processing group.

The defined parallel processing group has 6 Servers and they are configured to allow 50% of the available work processes to be used. 
Assuming each server has a total of 100 Work Processes available then parallel processing would allow a maximum of 50 work processes to be consumed.   My assumption is that when the 1st job to reach the parallel processing phase it will be allowed to consume up to 300 work processes based on availability, then next job will then either be allowed to consume the remaining 300 work processes or less, while the last two jobs get nothing.

Please advise and thanks for your time.

[former_member182466 · Accepted solution]

My understanding is that when you use the same group in SPBT_INITIALIZE and

CALL FUNCTION ... STARTING NEW TASK .... DESTINATION IN GROUP ....  you will never exceed the limit set by the group. And this limit is shared by all processes using the group. So, in your example all four jobs will share the 50 processes and depending on your implementation and timing of the jobs it might turn out that one job will grab all 50 while the others get 0.

I am curious if you see different results in your testing.

[cris_anderson · Accepted solution]

Thanks.   These are standard SAP Programs that are being executed via batch.   If I understand your comments correctly when all 4 jobs kick off and there are 50 work processes available for Parallel processing then all 4 Programs that are being started at the same time will share the 50 available work processes for parallel work.

[former_member802413]

Hi,

please help if you can give some inputs,

SAP Batch job parallel processing perfomance tune | SAP Community

regards,