DS run longer with scheduled job as compare to manual run

Question

I have scheduled a job through Management Console (MC) to run everyday once at 
certain time. After some time, maybe after 15 days of running, the execution 
time has increased to double from 17 mins to 67 mins by one time jump. After 
that, the job kept running and spent 67 mins to complete.
The nature of the job is to generate around 400 output flat files from a 
source db2 table. Under efficient running time, 1 file took around 2 seconds to 
generate. But now it became taking 8 seconds to generate one file. The data 
volume and nature of the source table didn't change, so that was not the root 
cause of increasing time.
I have done several investigations and the results as such:
1) I scheduled again this job at MC to run for testing, it would take 67 mins 
to complete. However, if I manually run this job thorough MC, it would take 
17 mins efficient time to run.
2) I replicated this job to a second job as a copy. Then I scheduled this 
copied job at MC to run, it would take 67 mins to run. But if I manually run 
this job through MC, it will take 17 mins to run.
3) I created another test repo and load this job in. I scheduled the job to 
run at this new repo, it would take 67 mins to run. If I manually run the job 
through MC, it only took 17 mins to run.
4) Finally, I manually executed the job through unix job scripts command, 
which is one of the scheduled job entry in the cron file, such as 
./DI__4c553b0d_6fe5_4083_8655_11cb0fe230f4_2_r_3_w_n_6_40.sh, the job also would take 17 
mins to run to finish.
5) I have recreated the repo to make it clean and reload back the jobs and 
recreated again the schedule. Yet it still took 67 mins to run scheduled job.
Therefore, the conclusion is why it takes longer time to run by scheduling 
method as compare to manually running method?
Please provide me a way to troubleshoot this problem. Thank you.
OS : HPUX 11.31
DS : BusinessObjects Data Services 12.1.1.0
databasee : DB2 9.1

Answer 1

Yesterday we had done another test and indirectly made the problem to go 
away. We changed the generated output flat file directory from current directory 
of /fdminst/cmbc/fdm_d/bds/gl to /fdminst/cmbc/fdm_d/bds/config directory to 
run, to see any difference would make. We changed the directory pointing 
inside Substitution Parameter Configurations windows. Surprisingly, job had 
started to run fast and completed in 15 minutes and not 67 minutes anymore.
Then we shifted back and pointed the output directory back to original 
/fdminst/cmbc/fdm_d/bds/gl and the job has started to run fast ever since and all 
completed in 15 minutes. Even we created ad hoc schedule to run and it was 
still running fast.
We not sure why it was solved by shifting directory away and shifting back, 
and whether this had to do with BODS problem or HP Unix system environment 
problem. Nonetheless, the job is started to run normally and fast now as we 
test.