To remove memory on a running LPAR, an active RMC connection to the HMCs is required. Memory can only be removed if the remaining amount of memory is greater than or equal to the minimum amount of main memory (min_mem).

Memory is removed, analogous to adding, with the corresponding command “lpar rmmem” (remove memory):

$ lpar rmmem aix22 2G
$

The prerequisite for this, however, is that 2 GB are either not used in the operating system or can be made free by paging out memory pages to the paging space.

Afterwards, only 4 GB of main memory are available in the LPAR:

aix22 # lsattr -El mem0
ent_mem_cap         I/O memory entitlement in Kbytes           False
goodsize       4096 Amount of usable physical memory in Mbytes False
mem_exp_factor      Memory expansion factor                    False
size           4096 Total amount of physical memory in Mbytes  False
var_mem_weight      Variable memory capacity weight            False
aix22 #