# Best Practice 15.3 – Modify SAP parameters to align with hardware selection
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Tuning SAP application parameters can help improve the performance of the application. These parameters are often dependent on the underlying hardware configuration and operating system type.

 ** Suggestion 15.3.1 – Allow SAP to self-tune according to `PHYS_MEMSIZE` ** 

 For recent versions of SAP software, using kernel release 7.40 or higher, self-tuning of certain parameters is possible and recommended. For instance, many parameters are derived via formulas related to the main memory available on an instance (PHYS\_MEMSIZE). This allows for automatic tuning of memory parameters when resizing an EC2 instance underlying the SAP software to meet changing performance requirements. 
+  SAP Documentation: [SAP Memory Management: Parameter Reference](https://help.sap.com/viewer/f146e75588924fa4987b6c8f1a7a8c7e/LATEST/en-US/493431b15cce5717e10000000a42189b.html) 
+  SAP Note: [2085980 – New features in memory management as of Kernel Release 7.40](https://launchpad.support.sap.com/#/notes/2085980) [Requires SAP Portal Access] 

 **Suggestion 15.3.2 – Review SAP swap space and maximum memory use** 

 When running SAP on AWS, overutilized swap space on disk can cause I/O credit exhaustion on Amazon EBS and lead to performance degradation. Evaluate the different [EBS storage options](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-volume-types.html) available on AWS and configure swap space to meet your performance needs. 
+  SAP Note: [1597355 - Swap-space recommendation for Linux](https://launchpad.support.sap.com/#/notes/1597355) [Requires SAP Portal Access] 
+  SAP Documentation: [Swap Space Requirements](https://help.sap.com/saphelp_nw73/helpdata/en/49/325e42e93934ffe10000000a421937/frameset.htm)