Configuring and Migrating Memory on vPars

5
Note that in the above examples, we have merely specified a memory size without any particular cell
information. Hence the memory is allocated from the ILM present on the system. Now, if we need to
add 2 GB of CLM from cell 0 to vpar1 and 1 GB of CLM from cell 1 to vpar2 and also add 2 CPUs
from cell 0 to vpar1 and 2 CPUs from cell 1 to vpar2, we would do the following:
# vparmodify –p vpar1 –a cell:0:mem::2048 –a cell:0:cpu::2
# vparmodify –p vpar2 –a cell:1:mem::1024 –a cell:1:cpu::2
Figure 1 below depicts this memory distribution for the above example on an HP Integrity server when
both vpar1 and vpar2 are live. The low end of the memory is at the left and the high end is at the
right in the figure. The system contains 4 GB of ILM starting from address 0, 2 GB of CLM from cell 0
starting from address 0x70000000000 and 2 GB of CLM from cell 1 starting from address
0x72000000000. Approximately 384 MB from address 0 is taken by the monitor and firmware on
this example system. Note: Memory consumed by the monitor and firmware can vary.
Figure 1 ILM and CLM Partitioning
ILM and CLM Guidelines
The following provides some guidelines on how to use ILM and CLM in a vPars system:
• If ease of management is the objective, configure all the memory as ILM unless one or more
partitions in the system are going to use applications that make use of locality APIs to optimize
performance. Having all memory as ILM makes it easier to assign and move memory and
processors between partitions.
• When configuring CLM on the system, make sure that there is enough ILM reserved for each
partition to load and run the kernel. The PA-RISC HP-UX kernel needs ILM to boot. Even though
on the HP Integrity server, HP-UX kernel might boot with just CLM, it is not a supported HP-UX
configuration.
• When configuring CLM and CLP for each partition, refer to the HP-UX NUMA documentation to
decide on how to optimize the performance [1,2].
• The vPars monitor does not do any distribution of processors and memory based on locality. It
requires the system administrator to use the CLM and CLP options to appropriately configure
partitions. Hence, when adding or removing CLM from a cell, take into consideration the CLP