By default, CPU folding is enabled in AIX. A system with cpu folding disabled may look like this:
[root@primary01 /]# schedo -a | grep vpm_xvcpus
vpm_xvcpus = -1
Enable vpm_xvcpus
To enable it, you can set vpm_xvcpus into 0.
[root@primary01 /]# schedo -o vpm_xvcpus=0
Setting vpm_xvcpus to 0
Let's check current value of vpm_xvcpus.
[root@primary01 /]# schedo -L vpm_xvcpus
NAME CUR DEF BOOT MIN MAX UNIT TYPE
DEPENDENCIES
--------------------------------------------------------------------------------
vpm_xvcpus 0 0 0 -1 1536 processors D
--------------------------------------------------------------------------------
Increase vpm_xvcpus
To increase the number of virtual processors permanently, say 2 to conform to requirements of some application installation like Oracle grid infrastructure 19c, we can do this:
[root@primary01 /]# schedo -p -o vpm_xvcpus=2
Setting vpm_xvcpus to 2 in nextboot file
Setting vpm_xvcpus to 2
[root@primary01 /]# schedo -L vpm_xvcpus
NAME CUR DEF BOOT MIN MAX UNIT TYPE
DEPENDENCIES
--------------------------------------------------------------------------------
vpm_xvcpus 2 0 2 -1 1536 processors D
--------------------------------------------------------------------------------
The change needs a system reboot to take effect.