Oracle Database 11g Release 2 Real Application Clusters with SLVM/RAW on HP-UX Installation Cookbook, September 2010

Prepare HP-UX Systems for Oracle software installation

On HP-UX, most processes use a time-sharing scheduling policy. Time sharing can have detrimental

effects on Oracle performance by descheduling an Oracle process during critical operations, for

example, when it is holding a latch. HP-UX has a modified scheduling policy, referred to as

SCHED_NOAGE, that specifically addresses this issue. Unlike the normal time-sharing policy, a process

scheduled using SCHED_NOAGE does not increase or decrease in priority, nor is it preempted.

This feature is suited to online transaction processing (OLTP) environments because OLTP environments

can cause competition for critical resources. The use of the SCHED_NOAGE policy with Oracle

Database can increase performance by 10 percent or more in OLTP environments.

The SCHED_NOAGE policy does not provide the same level of performance gains in decision support

environments because there is less resource competition. Because each application and server

environment is different, you should test and verify that your environment benefits from the

SCHED_NOAGE policy. When using SCHED_NOAGE, Oracle recommends that you exercise caution

in assigning highest priority to Oracle processes. Assigning highest SCHED_NOAGE priority to Oracle

processes can exhaust CPU resources on your system, causing other user processes to stop responding.

The RTSCHED and RTPRIO privileges grant Oracle the ability to change its process scheduling policy

to SCHED_NOAGE and also tell Oracle what priority level it should use when setting the policy. The

MLOCK privilege grants Oracle the ability to execute asynch I/Os through the HP asynch driver.

Without this privilege, Oracle9i generates trace files with the following error message: “Ioctl

ASYNCH_CONFIG error, errno = 1”.

As root, do the following:

• If it does not already exist, create the /etc/privgroup file. Add the following line to the file:

dba MLOCK RTSCHED RTPRIO

• Use the following command syntax to assign these privileges:

bike/cycle# setprivgrp -f /etc/privgroup

•  Create the /var/opt/oraInventory directory and make it owned by the oracle account. After

installation, this directory will contain a few small text files that briefly describe the Oracle software

installations and databases on the server. These commands will create the directory and give it

appropriate permissions:

bike/cycle# mkdir /var/opt/oraInventory

bike/cycle# chown oracle:dba /var/opt/oraInventory

bike/cycle# chmod 755 /var/opt/oraInventory

• Create the following Oracle directories:

– Local Home directory:

Oracle Clusterware:

bike/cycle# mkdir -p /var/opt/product/crs_r2

bike/cycle# chown –R oracle:dba /var/opt/product

bike/cycle# chmod –R 775 /var/opt/product

Oracle RAC

bike/cycle# mkdir –p /var/opt/oracle/rac_r2

bike/cycle# chown –R oracle:dba /var/opt/oracle

bike/cycle# chmod –R 775 /var/opt/oracle