After the kernel switch, we usually see certain jobs like DELETE_OLD_LOAD_FORMAT are scheduled automatically.
In this article we will discuss it’s cause and introduction to RKS procedure for kernel switch.
Problem Description:
- After Kernel switch, database space issue occurs since tables like REPOLOAD, D010INC grow suddenly.
- When analyzed in SM51, program RS_LOAD_FORMAT_ADM causes this issue.
- SAP job DELETE_OLD_LOAD_FORMAT was scheduled automatically.
Cause:
The RKS also known as rolling kernel switch was used to switch kernel.
What is Rolling Kernel Switch?
During the SAP kernel upgrade with multiple application server, we need to:
- Stop all the application servers including PAS.
- switch the kernel executable.
- restart the application instance.
This traditional approach has major disadvantage
Downtime is required during kernel switch.
To minimize this downtime, SAP introduced RKS (Rolling Kernel Switch) procedure.
Please refer my previous blog for detailed information about Rolling Kernel switch:
https://www.basisguru.com/rolling-kernel-switch-in-sap/
Delineation:
Whenever we perform Kernel switch, due to change in load format regeneration of ABAP programs is needed.
You may find useful information on ABAP load in my previous article:
SGEN SAP System Load Generator
If Rolling Kernel Switch procedure is used for kernel switch, old format is retained in DB in addition to the new load format as both of them is needed during transition.
Certain tables like REPOLOAD, D010INC, and D010TAB grow TEMPORARILY in this procedure.
The ABAP job DELETE_OLD_LOAD_FORMAT becomes active once app server starts with new kernel which executes program RS_LOAD_FORMAT_ADM.
References:
https://launchpad.support.sap.com/
https://help.sap.com/