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

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value than actual memory available. However this would allow a single process to outgrow a systems
main memory and cause extensive swapping and paging.
It is highly recommended to stay within the bounds of the available memory for this tunable
parameter, and never raise the tunable parameter to a value larger than the physical memory
available plus the configured swap space.
The recommended maximum value for per_proc_address_space is 0x40000000000.
The recommended value for max_per_proc_address_space is to set it to the same value as
per_proc_address_space with a maximum of 0x40000000000.
max_proc_per_user
This tunable parameter specifies the maximum number of processes a non-root user can create. To
disable the limits for this tunable parameter it can be set to 0. Disabling this limit has a slight
performance advantage.
The recommended value for max_proc_per_user is 1024. If the application environment requires
more than 1024 processes per user the value can be increased accordingly.
max_threads_per_user
This tunable parameter specifies the maximum number of threads a (non-root) user can create. To
disable the limits for this tunable parameter it can be set to 0. Disabling this limit has a slight
performance advantage.
The recommended value for max_threads_per_user is 4096. If the application environment
requires more than 4096 threads per user, the value can be increased accordingly.
maxusers
This tunable parameter is a generic base tunable parameter used to calculate the value of various
data structures, tables and other tunable values.
The recommended value for maxusers on AlphaServer ES40 class systems and higher is 8192. This
value can be increased to the maximum of 16384.
RT Subsystem
The aio_task_max_num parameter should be set in the rt subsystem section of
/etc/sysconfigtab. This tunable parameter specifies the maximum number of concurrent active
AIO tasks.
The current recommended value is 8193.
RDG Subsystem
Set the following tunable parameters in the rdg subsystem section of /etc/sysconfigtab.
Parameters in this section only apply to systems running Oracle RAC over RDG.
max_objs
HP recommends setting this tunable parameter to at least five times the number of Oracle processes
per node, and up to 10240 or the number of Oracle processes multiplied by 70, whichever is larger.
msg_size
HP recommends setting this tunable parameter equal to or greater than the maximum value of the
DB_BLOCK_SIZE parameter for the database. Oracle recommends a value of 32768 because
Oracle 9i and later support different block sizes for each table space.