IBM Power System POWER7 Series, Руководство по оптимизации и настройке

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POWER7 and Optimization and Tuning Guide
ra_fork() Forks a process that is attached to a specific work
component. The service uses
rstype_t and rsid_t to
specify the work component. However, the only supported
rstype_t is
R_RSET
.
ra_get_attachinfo()
ra_free_attachinfo()
These services retrieve the RSET attachments that are
attached to a memory range. The
ra_attachrset()
allows
RSET attachments to ranges of memory in a file or shared
memory segment. These services allow those attachments
to be queried.
ra_getrset() Retrieves the RSET attachment to a process or thread.
The return code indicates where the returned RSET
is attached.
ra_mmap() and ra_mmapv() Maps a file or memory region into a process and attaches
it to the resource set that is specified by the
rstype_t and
rsid_t parameters. A memory allocation policy similar to
ra_attachrset() allows a caller to specify how memory is
preferentially allocated when the area is accessed.
ra_shmget() and ra_shmgetv() Gets a shared memory segment with an attachment to a
resource set. The RSET is specified by the
rstype_t and
rsid_t parameters. A memory allocation policy similar to
ra_attachrset() allows a caller to specify how memory is
preferentially allocated when the area is accessed.
AIX Enhanced Affinity (Scheduler Resource Allocation Domain)
AIX Enhanced Affinity is a collection of AIX internal system changes and API extensions to
improve performance on POWER7 Systems. Enhanced Affinity improves performance by
increasing CPU and memory locality on POWER7 Systems. Enhanced Affinity extends the
AIX existing memory affinity support. AIX V6.1 technology level 6100-05 contains AIX
Enhanced Affinity support.
Enhanced Affinity status is determined during system boot and remains unchanged for the life
of the system. A reboot is required to change the Enhanced Affinity status. In AIX V6.1.0
technology level 6100-05, Enhanced Affinity is enabled by default on POWER7 machines.
Enhanced Affinity is available only on POWER7 machines. Enhanced Affinity is disabled by
default on POWER6 and earlier machines. A
vmo command tunable
( enhanced_memory_affinity ) is available to disable Enhanced Affinity support on
POWER7 machines.
Here are two concepts that are related to Enhanced Affinity:
򐂰
Scheduler Resource Allocation Domain (SRAD): SRAD is the collection of logical CPUs
and physical memory resources that are close from a hardware affinity perspective. An
AIX system (partition) can consist of one or more SRADs. An SRAD represents the same
collection of system resources as an existing MCM. A specific SRAD in a partition is
identified by a number. It is an
sradit_t
data type and is often referred to as an SRADID.
򐂰 SRADID: The numeric identifier of a specific SRAD. It is a short integer data type. An
SRADID value is the index of the resource allocation domain at the R_SRADSDL system
detail level in the system’s resource set topology.
Power Systems before POWER7 Systems provided only system topology information to
dedicated CPU logical partitions. This setup limited the usefulness of RSET attachments for
CPU and memory locality purposes to dedicated CPU partitions. POWER7 Systems provide
system topology information for shared CPU logical partitions (SPLPAR).