Locality-Optimized Resource Alignment

Figure 1. Resources available in the example nPartition

Dividing the nPartition into vPars instances of equal size

Suppose that it is desired to create six vPars instances of equal size in this partition. Since the

partition contains 24 cores, each vPars instance should have 4 cores. Since the partition contains 24

GB of interleaved memory and 168 GB of local memory, each vPars instance should have 4 GB of

interleaved memory and 28 GB of local memory. In practice, the actual memory allocations will be

somewhat smaller, due to the memory consumed by firmware and by the vPars monitor.

The commands that could be used to establish the processor and memory allocations are as follows:

vparcreate -p vp1 -a cpu::4 -a mem::4096 -a cell:1:mem::28672

vparcreate -p vp2 -a cpu::4 -a mem::4096 -a cell:1:mem::28672

vparcreate -p vp3 -a cpu::4 -a mem::4096 -a cell:2:mem::28672

vparcreate -p vp4 -a cpu::4 -a mem::4096 -a cell:2:mem::28672

vparcreate -p vp5 -a cpu::4 -a mem::4096 -a cell:3:mem::28672

vparcreate -p vp6 -a cpu::4 -a mem::4096 -a cell:3:mem::28672

Please note that the creation commands specify the cell identifiers for the local memory but only a

count for the number of processors. The enhancements added to vPars version A.05.05 (the version

delivered starting with Update 4) automatically allocate processor cores in close proximity to the

memory.

For this example, the processor and memory allocations would be as shown in the following diagram: