User Guide

IBM

Power

Power10 Quick-start Guide – Oracle Database w/ AIX Best Practices

Page Size

The general recommendation for most Oracle databases on AIX is to utilize 64KB page

size and not 16MB page size for the SGA. Typically, 64 KB pages yield nearly the same

performance benefit as 16 MB pages without special management.

VIOS & RAC Interconnect

A dedicated 10G (i.e, 10G Ethernet Adapter) connection is

recommended as minimum to provide sufficient bandwidth for

cluster timing sensitive traffic. RAC cluster traffic - interconnect

traffic should be dedicated and not shared. Sharing of interconnect

can cause timing delays leading to node hang/eviction issues.

Shared SYMTAB

The LDR_CNTRL=SHARED_SYMTAB=Y setting does not need to be specifically set in

11.2.0.4 or later releases. The compiler linker options take care of this setting and no

longer needs to be specifically set. It is not recommended to have

LDR_CNTRL=SHARED_SYMTAB=Y specifically set in 12c or later releases.

TNS Listener

Oracle 12.1 database and later releases by default will use 64k pages for text, data and

stack. However, for the TNSLISTENER it still uses 4k pages for text, data and stack. To

enable 64k page for the listener use the export command prior to starting the listener

process. Note that running in an ASM based environment that the listener runs out of

GRID_HOME and not ORACLE_HOME.

The documentation for the “srvctl setenv” command changed in 12.1 or later releases.

The -t or -T was removed in favor of -env or -envs. In the Oracle Listener environment set

and export:

- LDR_CNTRL=DATAPSIZE=64K@TEXTPSIZE=64K@STACKPSIZE=64K <tnslistener user >

- VMM_CNTRL=vmm_fork_policy=COR (add the ‘Copy on Read’ command)

Virtual Processor Folding

This is a critical setting in a RAC environment when using LPARs with

processor folding enabled. If this setting is not adjusted, there is a

high risk of RAC node evictions under light database workload

conditions. schedo -p -o vpm_xvcpus=2

Network Performance

This is a long-standing network tuning suggestion for Oracle on AIX,

although the default remains at 0. TCP Setting of rfc1323=1

More comprehensive information

Refer to link: Managing the Stability and Performance of current

Oracle Database versions running AIX on Power Systems including

POWER9

https://www.ibm.com/support/pages/node/6355543