SAP HANA- Parameters that Control Memory Consumption

The memorymanager section of the global.ini file contains parameters that allow you to control the memory consumption of SAP HANA.
In a system that supports multitenant database containers, you can configure the global.ini at both the system level and the database level. Parameters configured at the system level apply to the complete system and all databases. Parameters configured at the database level apply to the specified database only

[toggle title=”Parameter – global_allocation_limit” state=”open”]The global allocation limit limits the amount of memory that can be used by the system as a whole. The value is the maximum allocation limit in MB. Note:In a system that supports multitenant database containers, the global allocation limit configured at the system layer of the global.ini file is always effective regardless of any value configured at the database layer. [box type=”info” align=”” class=”” width=””]A missing entry or a value of 0 results in the system using the default settings. The global allocation limit is calculated by default as follows: 90% of the first 64 GB of available physical memory on the host plus 97% of each further GB. Or, in the case of small physical memory, physical memory minus 1 GB.[/box][/toggle]

[toggle title=”Parameter – allocationlimit” state=”open”]Collectively, all processes cannot consume more memory than the global allocation limit. The allocation limit limits the amount of memory that can be used by individual processes. The value is the maximum allocation limit in MB. [box type=”info” align=”” class=”” width=””]A missing entry or a value of 0 results in the system using the default settings. The default allocation limit is calculated in the same way as the default global allocation limit.[/box][/toggle]

[toggle title=”statement_memory_limit” state=”open”]When reaching the statement memory limit, a dump file is created with “compositelimit_oom” in the name. The statement is aborted, but otherwise the system is not affected. The unit of measure is GB.[/toggle]

 

[toggle title=”statement_memory_limit_threshold” state=”open”]The statement memory limit is applied if the current SAP HANA memory consumption exceeds the statement memory limit threshold as a percentage of the global allocation limit.[/toggle]

Reference:http://help.sap.com/hana/SAP_HANA_Troubleshooting_and_Performance_Analysis_Guide_en.pdf

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