Determining how much memory you have on IBM AIX

Question

Memory on AIX - How to use lsdev and lsattr to determine the amount of physical memory you have.

Answer

When tuning IBM® Informix® database servers you need to know the amount of memory on your IBM AIX® system. The values you use in the Shared Memory Parameters section of the onCONFIG configuration file determine the amount of memory the database server needs. The amount of memory on the computer limits how much memory the database server has available. 

On AIX you can use a combination of the commands lsdev and lsattr to determine how much memory the computer has. These commands (located in /usr/sbin) are used to display the system devices and their attributes. 


STEPS

1. Log in as user informix 

2. Run the command lsdev -C | grep mem

3. For each device displayed in step 2., run the command:

lsattr -El memX

memX
Device name from step 2.


Example:


This example is from a system with 3 GB of physical memory and one memory device named mem0.

$ lsdev -C | grep mem

mem0       Available 00-00        Memory


$ lsattr -El mem0

size   3072 Total amount of physical memory in Mbytes  False

Note: Please contact AIX support if you need additional help with these commands or other ways to identify the amount of memory on your computer.

https://www-304.ibm.com/support/docview.wss?uid=swg21143451