Locality-Optimized Resource Alignment

8
Glossary
Term Definition
Socket Receptacle on a motherboard for the physical package of processing resources.
Processor
core
If the physical package of processing resources includes multiple independent
functional entities, each of them is called a processor core.
Core
Same as processor core. The keyword ‘cpu’ in the vPars commands refers to a
core.
CPU Acronym for Central Processing Unit. The term processor core is preferred.
Cell
The basic physical building block of a system complex. A cell contains processor
sockets, memory, and I/O components.
Crossbar
A component of the interconnect fabric that allows the cells in a system complex to
communicate with each other.
Locality
domain
A set of processors, memory, and I/O system bus adapters identified by the
operating system for resource alignment purposes.
Locality Same as locality domain.
SMP
Acronym for Symmetric Multiprocessor. A model in which all of the processors in a
system are equivalent to and interchangeable with each other.
NUMA
Acronym for Non--Uniform Memory Architecture. A hardware platform in which
system memory is separated into localities based on memory access latency times
for processors.
ILM
Acronym for Interleaved Memory. A technique in which successive cache lines of
memory are drawn from different localities.
Technical details
The appendices that follow contain the technical details to supplement the general information
presented in the opening sections of this paper. The appendix
Configuring nPartitions for LORA
explains the steps needed for every deployment of LORA. The appendix
Configuring vPars for LORA
gives the additional steps needed when vPars is used in a LORA nPartition. Recommendations for
fine-tuning workloads are given in the appendix
Advanced tuning.
Configuring nPartitions for LORA
This appendix discusses converting an existing 100% interleaved partition for use with LORA, and
creating a new LORA partition to meet the needs of a specified workload. The details for configuring
a server complex and for dividing it into nPartitions are available in the
references.
Converting an existing nPartition for LORA
If an existing interleaved nPartition is to be converted for LORA, it is only necessary to configure each
base cell in the nPartition with 87.5% local memory. (Any floating cells always have 100% local
memory.)