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

shm_mni

This tunable parameter specifies the maximum number of shared memory regions that can be used on

the system at one time. When NUMA is enabled in Oracle, Oracle will allocate several shared

memory segments for each RAD. Oracle will allocate these segments for each instance running on the

system. This value should be large enough to cover all instances. This parameter is a limit, which does

not have performance implications.

The recommended value for shm_mni is 256.

shm_seg

This tunable parameter specifies the maximum number of System V shared memory regions that can

be attached to a single process at one time. The same guidelines as for shm_mni (see the previous

parameter) apply, but for one Oracle instance only.

The recommended value for shm_seg is 128.

INET Subsystem

Set the tunable parameters discussed in this section in the inet subsystem section of

/etc/sysconfigtab.

Additionally, follow the Best Practice for tuning Internet servers tips available from:

http://h30097.www3.hp.com/docs/best_practices/BP_INTUNING/TITLE.HTM

You can find recommendations specific to Gigabit Ethernet (GbE) performance in this Best Practice:

http://h30097.www3.hp.com/docs/best_practices/BP_GIGABIT/TITLE.HTM

udp_sendspace and tcp_sendspace

These tunable parameters specify the send buffer size for UDP and TCP requests. In environments

using Gigabit Ethernet (GbE) or very heavy network activity, you may want to set the value for these

tunable parameters to an even higher value than the system defaults (61440-for tcp_sendspace,

and -9216 for udp_sendspace).

These parameters should, at the very minimum, be set to twice the size of the largest Oracle data

block in use for Oracle RAC systems. It is safe to increase these parameters to 128 K, 256 K, or even

512 K when data is transferred between applications that use large socket buffers.

The recommended value for udp_sendspace and tcp_sendspace is 65536 (64 KB), unless the

application requires an even larger value.

udp_recvspace and tcp_recvspace

These tunable parameters specify the receive buffer size for UDP and TCP requests. In environments

using Gigabit Ethernet (GbE), or very heavy network activity, you may want to set the value for these

tunable parameters to an even higher default value than the suggest defaults.

These parameters should, at the very minimum, be set to twice the size of the largest Oracle data

block in use for Oracle RAC systems. It safe to increase these parameters to 128 K, 256 K, or even

512 K when data is transferred between applications that use large socket buffers.

The recommended value for udp_recvspace and tcp_recvspace is 65536 (64 KB, unless the

application requires an even larger value.

ipport_userreserved

This tunable parameter specifies the number of times a system can simultaneously make outgoing

connections to other systems. The number of outgoing ports is the value of the

ipport_userreserved attribute minus the value of the ipport_userreserved_min attribute.