Locality-Optimized Resource Alignment

The parmodify command is used to change the local memory ratio. For example, for an nPartition

built from cells 1, 2, and 3:

parmodify -p 2 -m 1:base:::87.5% -m 2:base:::87.5% -m 3:base:::87.5%

It is necessary to reboot the partition for the change to take effect. The man page for the

parmodify(1m) command has the full details.

Creating a new nPartition for LORA

Determine the size of the nPartition

Determine the size of the nPartition by estimating the amount of processing resources needed to

provision the application workload, in terms of number of processors, amount of memory, and the

number of I/O adapters. HP provides a variety of estimating tools, such as Capacity Advisor, to help

provision workloads. Alternatively, the estimate could be based on comparison to a similar

workload. Many workloads are CPU bound, so it is common to express the partition size as the

number of processor cores or processor sockets.

If iCAP or gWLM is to be used to manage the number of cores in the partition, then the maximum

number of cores or sockets should be used in the size estimate.

If the sizing guides or past experience assume interleaved memory, the estimates should be adjusted

for the special characteristics of LORA. Under LORA, processors are more efficient, because they

spend less time waiting for memory accesses to be satisfied, so fewer cores are needed. On the

other hand, to ensure that local memory is available on the cell where it is needed, the amount of

memory should be increased modestly. The following table gives the guidelines:

Table 1. Partition size adjustments for LORA

Number of

sockets

Core

adjustment

Memory

adjustment

1 to 12 None None

13 to 24 Reduce by 10% Increase by 5%

25 to 48 Reduce by 20% Increase by 10%

49 to 64 Reduce by 25% Increase by 15%

Note

If memory utilization is below 75%, it is not necessary to increase the

amount of memory at all.

Create the nPartition

The parconfig command is used to build the nPartition. For example, the following command

creates a partition that requires 24 processor cores:

parconfig –x -O HPUX_11iV3 –X LORA -n mincpus:24 -Z high_performance

The man page for the parconfig(1m) command has the full details.