In my landscape SAP is running on HPUX. We have clustered environment. Oracle is on different host. We have having performance issue in SAP application host because of memory. All the time memory is more than 95% used. RAM is 16GB and virtual memory is 24GB. Now to improve the performance we need to upgrade system RAM. I am not very much sure how to calculate how much more RAM is required. Shall I upgrade it from 16 to 24GB? Is there any calculations which helps to find out how much RAM needed in a server.
I think the monitoring should be done via the standard transaction, i.e ST02, ST03, ST06, ST04 to determine the usage and workload.
But do refers to standard SAP note on HPUX, i.e:
172747 SAP on HP-UX: OS kernel parameter recommendations
1075118 SAP on HP-UX: FAQ
146528 Configuration of R/3 on hosts with much RAM
1112627 SAP on HP-UX: Recommendations for swap and pseudo swap
837670 Minimum OS patch recommendations for HP-UX
Hope this helps.
Some memory tools for your analysis:
ST02 -> Detailed Analysis Menu -> SAP Memory
-> Ext. Memory Blocks & Mode List, allow you to monitor memory.
SM04 -> Goto -> Memory gives you a snapshot of memory being used but
Note #649327 (Analysis of memory consumption) also gives related
By calling Transaction SM04 and choosing 'Goto' -> 'Block list',
you can display an overview of the current roll and paging memory
levels resulting from active users and their transactions. Try to
decide from this whether another program requires a lot of memory
space (perhaps too much). Also st02 is useful also.