Creating the shared memory pool

You can create the shared memory pool by using the Hardware Management Console (HMC).

In the following procedure, a shared memory pool with a size of 20 GB and nine paging devices is created. Paging devices are disks provided through a storage area network (SAN) and mapped on two Virtual I/O Server (VIOS) partitions. A paging device is required for each shared memory partition for the shared memory pool to accommodate nine shared memory partitions.

To create the shared memory pool, complete the following steps:

1. On the HMC, select the managed system on which the shared memory pool will be created.
2. Right-click the HMC, and select Configuration > Shared Memory Pool Management. The Welcome window is shown. Click Next to continue.
3. Enter the pool size in the Pool size field and the maximum pool size in the Maximum pool size field. Click Next to continue. The Paging VIOS window appears.

   The pool size that you enter must be smaller than the amount of available system memory. The memory used by dedicated memory partitions cannot be used for the shared memory pool. In this case, the pool is created on a managed system where a pool larger than 62.8 GB cannot be created. Keep the maximum pool size to the required minimum value because for each 16 GB of pool memory, the hypervisor reserves 256 MB of memory for page tracking.

   Note: Paging space devices can be assigned only to one shared memory pool at a time. You cannot assign the same paging space device to a shared memory pool on one system and to another shared memory pool on another system at the same time.
4. From the VIOS list, select the required VIOS and click Next to continue. The Paging Space Devices window is shown.
   Note: You can select a maximum of two paging VIOS partitions for redundancy.
5. Click Select Devices.
6. Click Refresh to display the list of available paging devices. Select the paging devices to assign to the shared memory pool and click OK. The Summary window appears.
7. Click Finish to start the creation of the shared memory pool.

You can view the shared memory pool by using the lshwres command on the HMC command line interface. The attributes of the shared memory pool are displayed by using the -r mempool flag.

The attributes and status of each paging device are displayed by using the lshwres command with the -rsubtype pgdev flag.