lora(7)lora(7)NAMElora - Locality-Optimized Resource Alignment (LORA) framework
DESCRIPTION
an acronym for Locality-Optimized Resource Alignment, is a framework
for exploiting the locality domains in HP Non-Uniform Memory Architec‐
ture (NUMA) servers to improve performance or to reduce cost. On NUMA
servers, a locality domain can consist of a related collection of pro‐
cessors, memory, and peripheral resources. All processors in a given
locality domain will have equal or close to equal latency to any mem‐
ory.
LORA consists of a set of configuration rules, commands and tools to
simplify the configuration process, and a new HP-UX kernel mode. The
two HP-UX modes are called LORA mode and SMP (Symmetric Multiprocessor)
mode. SMP mode is characterized by balanced utilization of all system
processing resources, although the scheduler does account for system
topology in processor scheduling decisions.
In LORA mode, HP-UX attempts to align the processing resources execut‐
ing an application within the minimal set of locality domains. This
alignment results in improved application performance, or, alterna‐
tively, comparable performance with fewer processing resources.
The use of LORA is recommended for and is generally beneficial to all
workloads that exhibit locality of memory reference. The exception is
technical applications that operate on extremely large data sets. The
use of LORA requires the installation of a set of patches documented in
the HP-UX 11i Version 3 September 2009 Release Notes.
The command can be used to establish server configurations that conform
to the LORA rules.
The command can be used to reestablish good resource alignment if it
has been disrupted by a major workload transition or platform reconfig‐
uration event.
The kernel tunable parameter can be used to control the HP-UX mode.
The kernel tunable parameter can be used to control the LORA memory
allocation policies.
The kernel tunable parameter can be used to control the LORA process
launch policies.
The tuning recommendations for LORA are as follows:
(1) Leave the parameter at its default value of 0.
(2) Leave the parameter at its default value of 0.
(3) Leave the parameter at its default value of 1.
(4) Apply the Server-Tunables product from the Tune-N-Tools bun‐
dle.
AUTHOR
was developed by HP.
SEE ALSOloratune(1M), parconfig(1M), numa_mode(5), numa_policy(5),
numa_sched_launch (5).
a detailed white paper is available at
lora(7)
