Manages Reliability, Availability, Serviceability parameters.
raso [-p | -r] [-y] [-o Tunable [= Newvalue] ]
raso [-p | -r] [-y] [-d Tunable]
raso -h [Tunable]
The raso command is used to configure Reliability, Availability, Serviceability tuning parameters. The raso command sets or displays the current or next-boot values for all RAS tuning parameters. The raso command can also be used to make permanent changes or to defer changes until the next reboot. The specified flag determines whether the raso command sets or displays a parameter. The -o flag can be used to display the current value of a parameter or to set a new value for a parameter.
Understanding the Effect of Changing Tunable Parameters
Misuse of the raso command can cause performance degradation or operating system failure. Before modifying any tunable parameter, you should first carefully read about all of the parameter's characteristics in the Tunable Parameters section in order to fully understand the parameter's purpose. You should then ensure that the Diagnosis and Tuning sections for this parameter actually apply to your situation and that changing the value of this parameter could help improve the performance of your system. If the Diagnosis and Tuning sections both contain only "N/A", it is recommended that you do not change the parameter unless you are specifically directed to do so by AIX® development.
Item | Description |
---|---|
-a | Displays the current, reboot (when used in conjunction with the -r flag), or permanent (when used in conjunction with the -p flag) values for all tunable parameters, with one tunable parameter per line displayed in pairs as Tunable = Value. For the permanent option, a value is only displayed for a parameter if its reboot and current values are equal. Otherwise NONE is displayed as the value. |
-d Tunable | Resets Tunable to the default value. If Tunable needs to be changed (that is, it is currently not set to its default value) and is of type Bosboot or Reboot, or if it is of type Incremental and has been changed from its default value, and the -r flag is not used in combination, Tunable is not changed and a warning displays. |
-D | Resets all tunables to their default values. If any tunables that need to be changed are of type Bosboot or Reboot, or if any tunables that need to be changed are of type Incremental and have been changed from their default value, and -r is not used in combination, these tunables are not changed and a warning displays. |
-F | Forces restricted tunable parameters to be displayed when the options -a, -L or -x are specified alone on the command line. If you do not specify the -F flag, restricted tunables are not included, unless they are specifically named in association with a display option. |
-h Tunable | Displays help about the raso command if no Tunable parameter is specified. Displays help about the Tunable parameter if a Tunable parameter is specified. |
-L Tunable | Lists the characteristics of one or all tunables,
with one tunable displayed per line using the following format:
|
-o Tunable [ =Newvalue ] | Displays the value or sets Tunable to Newvalue.
If Tunable needs to be changed (the specified
value is different than current value) and is of type Bosboot or Reboot,
or if Tunable if it is of type Incremental
and its current value is larger than the specified value, and if the -r flag
is not used in combination, Tunable is not
changed and a warning displays. If the -r flag is used in combination without a new value, the nextboot value for Tunable is displayed. If the -p flag is used in combination without a new value, a value is displayed only if the current and next boot values for Tunable are the same. Otherwise, NONE is displayed as the value. |
-p | When the -p flag is
used in combination with the -o, -d,
or -D flag, changes apply to both the current
and reboot values (in addition to the current value being updated,
the /etc/tunables/nextboot file is updated).
These combinations cannot be used on Reboot and Bosboot type parameters
because the current values for these parameters cannot be changed. When the -p flag is used with the -a or -o flag without specifying a new value, values are displayed only if the current and next boot values for a parameter are the same. Otherwise, NONE is displayed as the value. |
-r | When the -r flag is
used in combination with the -o, -d,
or -D flag, changes apply to reboot values
(the /etc/tunables/nextboot file is updated).
If any parameter of type Bosboot is changed, you are prompted to run
the bosboot command. When the -r flag is used with the -a or -o flag and a new value is not specified, the next boot values for tunables are displayed instead of the current values. |
-x Tunable | Lists the characteristics of one
or all tunables, with one tunable displayed per line using the following
format (spreadsheet format):
where Tunable is the tunable parameter, Current is
the current value of the tunable parameter, Default is the
default value of the tunable parameter, Reboot is the reboot
value of the tunable parameter, Minimum is the minimum value
of the tunable parameter, Maximum is the maximum value of
the tunable parameter, Unit is the tunable unit of measure,
Type is the parameter type, and Dependencies is the
list of dependent tunable parameters. If you make any change (with -o, -d, or -D) to a parameter of type Mount, it results in a warning message that the change is only effective for future mountings. If you make any change (with -o, -d or -D) to a parameter of type Connect, it results in inetd being restarted, and a warning message that the change is only effective for future socket connections. If you make any change (with -o, -d, or -D) to a parameter of type Bosboot or Reboot without -r, it results in an error message. If you make any change (with -o, -d, or -D but without -r) to the current value of a parameter of type Incremental with a new value smaller than the current value, it results in an error message. |
-y | Suppresses the confirmation prompt before running the bosboot command. |
If you make any change (with -o, -d or -D) to a restricted tunable parameter, it results in a warning message that a tunable parameter of the restricted-use type has been modified. If you also specify the -r or -p options on the command line, you are prompted for confirmation of the change. In addition, at system reboot, the presence of restricted tunables in the /etc/tunables/nextboot file, which were modified to a value that is different from their default value (using a command line specifying the -r or -p options), results in an error log entry that identifies the list of these modified tunables.
Item | Description | |
---|---|---|
Abbreviation | Prefix | Power of 2 |
K | kilo | 210 |
M | mega | 220 |
G | giga | 230 |
T | tera | 240 |
P | peta | 250 |
E | exa | 260 |
Item | Description |
---|---|
Dynamic | If the parameter can be changed at any time |
Static | If the parameter can never be changed |
Reboot | If the parameter can only be changed during reboot |
Bosboot | If the parameter can only be changed by running bosboot and rebooting the machine |
Mount | If changes to the parameter are only effective for future file systems or directory mounts |
Incremental | If the parameter can only be incremented, except at boot time |
Connect | If changes to the parameter are only effective for future socket connections |
Note that the current set of parameters managed by the schedo command only includes Dynamic and Reboot types.
When running in pre 5.2 compatibility mode (controlled by the pre520tune attribute of sys 0, see
NFS tuning on the client in the AIX Version 7.1 Performance management, reboot values for parameters, except those of type Bosboot, are not really meaningful because in this mode they are not applied at boot time.
In pre 5.2 compatibility mode, setting reboot values to tuning parameters continues to be achieved by imbedding calls to tuning commands in scripts called during the boot sequence. Parameters of type Reboot can therefore be set without the -r flag, so that existing scripts continue to work.
This mode is automatically turned ON when a machine is MIGRATED to AIX 5.2. For complete installations, it is turned OFF and the reboot values for parameters are set by applying the content of the /etc/tunables/nextboot file during the reboot sequence. Only in that mode are the -r and -p flags fully functional. See Kernel Tuning in the AIX Version 7.1 Performance Tools Guide and Reference for more information.
For default values and range of values for tunables, refer the raso command help (-h <tunable_parameter_name>).
Item | Description |
---|---|
kern_heap_noexec |
|
kernel_noexec |
|
mbuf_heap_noexec |
|
mtrc_commonbufsize |
|
mtrc_enabled |
|
mtrc_rarebufsize |
|
tprof_cyc_mult |
|
tprof_evt_mult |
|
tprof_inst_threshold |
|
tprof_evt_system |
|
raso -L
raso -r -o mtrc_enabled=0
raso -h mtrc_commonbufsize
raso -r -o tprof_inst_threshold=10000
raso -p -D
raso -r -a