IBM Power System POWER7 Series, Руководство по оптимизации и настройке

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POWER7 and Optimization and Tuning Guide
Permitted values for this environment variable are shown in Table 4-2
Table 4-2 DSO ASO_OPTIONS environment variable
Multiple options can be combined, as in the following example:
$ export ASO_OPTIONS="ALL=OFF,CACHE_AFFINITY=ON"
System requirements
ASO/DSO optimizations can be limited based on system configuration. Here are the
significant requirements and limitations:
򐂰 ASO and DSO takes advantage of a number of hardware features, and is supported only
on POWER7 running in native mode.
򐂰 ASO and DSO is integrated tightly with the AIX kernel, so various optimizations are
supported at different operating system levels. The minimum levels for cache and memory
affinity optimization are AIX V7.1 TL1 SP1 or AIX V6.1 TL8. Memory prefetch and large
page optimization require the installation of the DSO package that is supported on AIX
V7.1 TL2 SP1 and AIX V6.1 TL8 SP1.
򐂰 If it is running in a dedicated processor environment, virtual processor management (core
folding) must be disabled, which is the default. Enabling PowerSaver mode on the HMC
causes virtual processor management in a dedicated environment to be enabled (forcing
cache and memory affinity optimizations to be disabled).
򐂰 Enabling active memory sharing disables all optimizations except memory prefetch.
򐂰 Enabling active memory expansion disables memory affinity and large page optimization.
򐂰 In an SPLPAR environment, when CPU resources are capped, the system entitlement
must be a minimum of two cores for all but memory prefetch. Memory prefetch requires
eight cores.
򐂰 For large page and memory prefetch optimization, the system should have a minimum of
20 GB system memory.
Option Values Effect
ALL ON, OFF Enables or disables all ASO optimization. Options are
processed left to right; redundant or conflicting options
use the rightmost setting.
CACHE_AFFINITY ON, OFF Enables or disables the cache affinity optimization.
MEMORY_AFFINITY
ON, OFF Enables or disables the memory affinity optimization. The
memory affinity optimization is applied only if the cache
affinity optimization is also applied.
LARGE_PAGE ON, OFF Enables or disables 16 MB MPSS optimization.
MEMORY_PREFETCH
ON, OFF Enables or disables data stream prefetch optimization.
<unset> ON, OFF All optimization is enabled.
<any other values>
ON, OFF An undefined variable.