Inconsistent run time for a simple job in Production

[vinothkumar]

Hi all,
We have a simple job with source as DB2 and target as Teradata.
Change capture stage is used to identify the delta records. Oracle connector is involved to generate audit fields. This job is a multi instance one.
Job is running fine without any issues but it is taking more time than expected. It is taking more time on Sun-Thu whereas job runs faster on friday. If I see the job log below steps is taking more time.

Timestamo MessageId Message
2/19/2013 6:23:42 AM IIS-DSEE-TOSH-00002 main_program: orchgeneral: loaded
orchsort: loaded
orchstats: loaded
2/19/2013 6:27:21 AM IIS-DSEE-TDOR-00303 main_program: IS8.1 Oracle EE Stage (last fix: JR32340) built on 2010-05-12 for linux-suse.
Connected to Oracle server 9.2.0.8.0 using Oracle client 10.2.0.2.0.
Oracle session NLS parameters: LANG=POSIX NLS_LANG=AMERICAN_AMERICA.WE8ISO8859P1 NLS_LANGUAGE=AMERICAN NLS_TERRITORY=AMERICA NLS_CURRENCY=$ NLS_ISO_CURRENCY=AMERICA NLS_NUMERIC_CHARACTERS=., NLS_CALENDAR=GREGORIAN NLS_DATE_FORMAT=DD-MON-RR NLS_DATE_LANGUAGE=AMERICAN NLS_CHARACTERSET=US7ASCII NLS_SORT=BINARY NLS_TIME_FORMAT=HH.MI.SSXFF AM NLS_TIMESTAMP_FORMAT=DD-MON-RR HH.MI.SSXFF AM NLS_TIME_TZ_FORMAT=HH.MI.SSXFF AM TZR NLS_TIMESTAMP_TZ_FORMAT=DD-MON-RR HH.MI.SSXFF AM TZR NLS_DUAL_CURRENCY=$ NLS_NCHAR_CHARACTERSET=AL16UTF16 NLS_COMP=BINARY NLS_LENGTH_SEMANTICS=BYTE NLS_NCHAR_CONV_EXCP=FALSE.

What will be the reason for this.

[ray.wurlod]

Short answer - a different total machine load on Friday.