Before you configure the shared memory pool and create
logical partitions that use shared memory (hereafter referred to as shared
memory partitions), you need to determine the size of the shared
memory pool, the number of shared memory partitions to assign to the
shared memory pool, and the amount of memory to assign to each shared
memory partition.
To prepare to configure the shared memory
pool and shared memory partitions, complete the following steps:
- Assess your needs, take inventory
of your current environment, and plan for capacity. For instructions,
see Planning for logical partitions. More specifically, determine
the following information:
- Determine the number of shared memory partitions to
assign to the shared memory pool.
- Determine the amount of logical memory to assign as
the desired, minimum, and maximum logical memory for each shared memory
partition. You can apply the same general guidelines that
you might use to assign the desired, minimum, and maximum dedicated
memory to logical partitions that use dedicated memory. For example:
- Do not assign the maximum logical memory to a value that is higher
than the amount of logical memory that you plan to dynamically add
to the shared memory partition.
- Set the minimum logical memory to a value that is high enough
for the shared memory partition to successfully activate.
- Determine the amount of physical memory
to assign to the shared memory pool. For instructions,
see Determining the size of the shared memory pool.
- Determine the paging storage pool to assign to the shared
memory pool. The paging storage pool provides the paging space devices
for the shared memory partitions that are assigned to the shared memory
pool. The paging storage pool can contain paging space
devices and virtual disks. However, you cannot use the same logical
volume as both a paging space device and as a virtual disk at the
same time. Consider reserving an entire storage pool for paging space
devices.
- Optional: Determine the number of paging space
devices to assign to the shared memory pool and the size of each device. If you do not assign paging space devices to the shared memory
pool, Integrated Virtualization Manager automatically
creates them for you from the paging storage pool when you create
the shared memory partitions. If you decide to manually create the
paging space devices, consider the following requirements:
- You need to assign a minimum of one paging space device to the
shared memory pool for each shared memory partition.
- For AIX® and Linux Linux shared
memory partitions, the paging space device must be at least the size
of the maximum logical memory size of the shared memory partition
that you identified in step 1b. For example, you plan to create an AIX shared memory partition
with a maximum logical memory size of 16 GB. The paging space device
must be at least 16 GB.
- For IBM® i shared memory partitions,
the paging space device must be the size of the maximum logical memory
size of the shared memory partition that you identified in step 1b
multiplied by 129/128. For example, you plan to create an IBM i shared memory partition
with a maximum logical memory size of 16 GB. The paging space device
must be at least 16.125 GB.
