Solution : https://service.sap.com/sap/support/notes/386605 (SAP Service marketplace login required)
Summary :
With the introduction of Linux kernel 2.4, SAP has enhanced memory management techniques for 32-bit systems, allowing the efficient utilization of available memory. The kernel introduces options for managing user contexts via extended memory, supporting approximately 500 MB per session, crucial for facilitating the dynamic demands of SAP environments. This upgrade, utilizing instance profile parameters like 'es/implementation=map' or 'es/implementation=std', enhances existing methodologies by limiting the shared memory required for user contexts, significantly improving memory allocation and process efficiency. These advancements assist in overcoming the constraints posed by the standard 1 GB kernel space allocation in a total 4 GB addressable space on 32-bit architectures. The correlation between these parameters and SAP's overall performance underscores the necessity to optimize system configurations to leverage these capabilities fully. For robust memory handling, SAP recommends setting the 'es/implementation=map' for better memory management based on the improved kernel functionalities.
Key words :
administration-friendly extended memory administration based, instance profile parameter es/implementation=std, instance profile parameter es/implementation=map, fully occupy provided ztta/roll_extension, explicitly setting es/implementation=std, tmpfs /dev/shm tmpfs size=<size> 0 0, sap shared memory segments varies, theoretical address space restrictions apply, administration-friendly parameter management, red hat enterprise linux 2
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