Tuning HP Tru64 UNIX V5.1A and V5.1B for Oracle

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Although Oracle 8.1.7 Oracle Parallel Server (OPS) does support the use of RDG for communication
it is not recommended to enable RDG and to continue to use UDP instead.
The following commands show how to enable/disable the different protocols for IPC.
To enable Oracle RAC:
cd $ORACLE_HOME/rdbms/lib
For Oracle 8i:
make -f ins_rdbms.mk ops_on
make –f ins_rdbms.mk ioracle
For Oracle 10g/9i:
make -f ins_rdbms.mk rac_on
make -f ins_rdbms.mk ioracle
To use the UDP Protocol for IPC (the default for Oracle 8i):
make -f ins_rdbms.mk ipc_udp
make -f ins_rdbms.mk ioracle
To use RDG Protocol for IPC (the default for Oracle 9i):
make -f ins_rdbms.mk rac_on
make -f ins_rdbms.mk ioracle
Selecting NUMA Support in Oracle
When a single Oracle instance is used in more than 2 QBBs on large EV6 based NUMA systems,
such as the GS160 and the GS320, it may be advantageous to enable NUMA mode in Oracle as
well. This reduces the amount of references to memory in other QBBs and can substantially improve
performance. However, there is additional management overhead associated with it as well, which
consists of at least some of the following items:
• Oracle must be rebuilt to include NUMA support (see below).
• Oracle will split the fixed, variable, and block buffer areas in the SGA into different shared memory
segments. Oracle will also distribute these shared memory segments over each QBB in the system
and allocate separate shared memory segments to do so. This will significantly increase the number
of shared memory segments that need to be allocated for the instance.
• The Oracle db_writers parameter should be set to the number of QBBs in the system, and each
QBB should have a storage adapter that has connectivity to all the necessary storage for Oracle.
Not all of the QBBs may have storage connectivity, so db_writers should be set to the number of
QBBs that do have storage connectivity. Oracle will allocate the specified number of DB writer
processes evenly over the QBBs, for example, if db_writers is set to 2 in a 4-QBB system, then
Oracle will allocate 2 DB writer processes and bind one to QBB 0 and one to QBB 2. Make sure
that QBBs with storage connectivity match the QBBs to which Oracle has bound the DB writer
processes as this may require hardware reconfiguration if they do not match.
On large EV7 based systems (ES80 and GS1280) it is also possible to achieve a very small
performance benefit from enabling NUMA mode in a large single Oracle instance. HP does not
recommend enabling Oracle NUMA mode on EV7 based systems.
To enable NUMA support in Oracle 10g, Oracle 9i, or Oracle 8i, enter the following commands:
cd $ORACLE_HOME/rdbms/lib
make -f ins_rdbms.mk numa_on
make -f ins_rdbms.mk ioracle
To disable NUMA support in Oracle 10g, Oracle 9i, or Oracle 8i, enter the following commands: