SMIT Help Information for Performance & Resource Scheduling

Note: The information contained in this article is structured as help information for the System Management Interface Tool (SMIT) and is not intended for use as a procedural or conceptual article.

Resource Status & Monitors

You can report system activity, show process status, show virtual memory statistics, or show input/output statistics.


Analysis Tools

You can show system activity while running a command, or start or stop tracing, or generate a trace report.


Report System Activity

The sar command writes to standard output the contents of selected cumulative activity counters in the operating system


The sar command writes to standard output the contents of selected cumulative activity counters in the operating system


Interval LENGTH of each system activity sampling

The accounting system, based on the values in the Number and Interval parameters, writes information the specified number of times spaced at the specified intervals in seconds. The default sampling interval for the Number parameter is value 1 second


The accounting system, based on the values in the Number and Interval parameters, writes information the specified number of times spaced at the specified intervals in seconds. The default sampling interval for the Number parameter is value 1 second


Report ALL activities listed below?

Reports all data.


Report use of FILE ACCESS system routines?

Reports use of file access system routines specifying how many times per second several of the system file access routines have been called. The following values are accepted:

dirblk/s - Number of 512 byte blocks read by the directory search routine to locate a directory entry for a specific file.

iget/s - Calls to any of several i-node look-up routines that support multiple file system types. The iget routines return a pointer to the i-node structure of a file or device.

lookuppn/s - Calls to the directory search routine that finds the address of a v-node given a path name.


Report BUFFER ACTIVITY for transfers, accesses, and cache hit ratios?

Reports buffer activity for transfers, accesses, and cache (kernel block buffer cache) hit ratios per second. Access to most files in Version 3 bypasses kernel block buffering, therefore not generating these statistics. However, if a program opens a block device or a raw character device for I/O, traditional access mechanisms are used making the generated statistics meaningful. The following values are accepted:

bread/s, bwrit/s - Reports the number of block I/O operations.

lread/s, lwrit/s - Reports the number of logical I/O requests. Because logical I/O requests can result in more data being physically accessed than was requested, additional data may be held in the cache, from which it can be retrieved for the next logical I/O request, resulting in no further physical I/O.

pread/s, pwrit/s - Reports the number of I/O operations on raw devices.

%rcache, %wcache - Reports caching effectiveness (cache hit percentage). This percentage is calculated as [(100)x(lreads - breads)/(lreads)].


Report SYSTEM CALLS?

Reports system calls. The following values are accepted:

exec/s, fork/s - Reports the total number of fork and exec system calls.

sread/s, swrit/s - Reports the total number of read/write system calls.

rchar/s, wchar/s - Reports the total number of characters transferred by read/write system calls.

scall/s - Reports the total number of system calls.


Report KERNEL activity?

Reports kernel process activity. The following values are accepted:

kexit/s - Reports the number of kernel processes terminating per second.

kproc-ov/s - Reports the number of times kernel processes could not be created because of enforcement of process threshold limit.

ksched/s - Reports the number of kernel processes assigned to tasks per second.


Report MESSAGE and SEMAPHORE activities?

Reports message and semaphore activities per second. The following values are accepted:

msg/s - Reports the number of IPC message primitives.

sema/s - Reports the number of IPC semaphore primitives.


Report System Activity per Processor

Reports system activity only on specified processors.


Processor IDs

A list of processor identifiers.


Report AVERAGE QUEUE LENGTH while occupied, and percentage of time occupied?

Reports queue statistics. The following values are accepted:

runq-sz - Reports the average number of processes kernel threads in the run queue.

%runocc - Reports the percentage of the time the run queue is occupied.

swpq-sz - Reports the average number of processes kernel threads waiting to be paged in.

%swpocc - Reports the percentage of the time the swap queue is occupied.


Report PAGING statistics?

Reports paging statistics. The following values are accepted:

cycle/s - Reports the number of page replacement cycles per second.

fault/s - Reports the number of page faults per second. This is not a count of page faults that generate I/O, because some page faults can be resolved without I/O.

slots - Reports the number of free pages on the paging spaces.

odio/s - Reports the number of nonpaging disk I/Os per second.


Report CPU activity?

Reports system unit activity. The following values are accepted:

%idle - Reports the percentage of time the system unit wascpu or cpus were idle with no outstanding disk I/O requests.

%sys - Reports the percentage of time the system unitcpu or cpus spent in execution at the system (or kernel) level.

%usr - Reports the percentage of time the system unitcpu or cpus spent in execution at the user (or application) level.

%wio - Reports the percentage of time the system unit was idle waitingcpu or cpus were idle and the system was waiting for disk I/O to complete.

Note: The sar command reports system unit activity if no other specific content options are requested.


Report status of TEXT, PROCESS, i-node, and FILE TABLES?

Reports status of the process, i-node, and file tables.

file-sz, inod-sz, proc-sz - Reports the number of entries in use for each table.


Report SYSTEM SWITCHING activity?

Reports system switching activity.

pswch/s - ProcessContext switches per second.


Report TTY DEVICE activity?

Reports tty device activity per second.

canch/s - Reports tty canonical input queue characters. This field is always 0 (zero) for &Symbol.AIX; for Version 4 and higher.

mdmin/s - Reports tty modem interrupts.

outch/s - Reports tty output queue characters.

rawch/s - Reports tty raw input queue characters.

revin/s - Reports tty receive interrupts.

xmtin/s - Reports tty transmit interrupts.


Show System Activity While Running a Command

Reports, in seconds, the elapsed time, user time, and system execution time for a command.


The timex command reports, in seconds, the elapsed time, user time, and system execution time for a command. With specified flags, the timex command lists or summarizes process accounting data for a command and all of its children.


COMMAND name

Command is the name of any executable file on the system.


Provides options for managing kernel and network tuning parameters. These options allow you to list or change current or next boot values.


Provides options for displaying, resetting, saving and restoring all tuning parameters, together with special files. Special files are /etc/tunables/nextboot, which contains parameters for the next boot, /etc/tunables/lastboot, which contains parameters as they were at the last boot time, and /etc/tunables/lastboot.log, which contains all the changes made to tuning parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot tuning scheduler parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot virtual memory tuning parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot network tuning parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot NFS tuning parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot I/O tuning parameters.


Displays all parameters as they were the last time the system was booted.


Displays all changes made on tunable parameters.


Saves all the current parameters in the special file /etc/tunables/nextboot for the system to use the next time it is booted.


Saves all the current parameters in a new file with a name you provide. This file becomes the /etc/tunables/nextboot special file when you choose the "Restore All Current Parameters from Saved Values" option. The description field provides information about the file and helps you manage your files.


Sets all the current parameters to what they were the last time the system was booted.


Sets all the current parameters to the values that are in the selected file.


Changes all the current kernel and network tuning parameters to their default values.


Saves all the next boot parameters in the selected file in a new special file. This action is the same as copying the /etc/tunables/nextboot file to the /etc/tunables/selected file.


Sets the tunable parameters for the next boot to the values they were when the system was last booted.


Sets the next boot tunable parameters to the values saved in a selected file.


Sets the next boot tunable parameters to their default values.


Displays the following characteristics and dependencies of the current scheduler and memory load control tunable parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current scheduler and memory load control tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot scheduler and memory load control tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current scheduler and memory load control tunable parameters in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current scheduler and memory load control tunable parameters to their default values.


Changes the next boot scheduler and memory load control tunable parameters to their default value.


Displays the following characteristics and dependencies of the current virtual memory tunable parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current virtual memory tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot virtual memory tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current virtual memory tunable parameters in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current virtual memory tunable parameters to their default value.


Changes the next boot virtual memory tunable parameters to their default values.


Displays the following characteristics and dependencies of the current network tunable parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current network tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot network tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current network tunable parameters in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current network tunable parameters to their default value.


Changes the next boot network tunable parameters to their default values.


Displays the following characteristics and dependencies of the current NFS tunable parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current NFS tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot NFS tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current NFS tunable parameters in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current NFS tunable parameters to their default value.


Changes the next boot NFS tunable parameters to their default values.


Displays the following characteristics and dependencies of the current I/O tunable parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current I/O tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot I/O tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current I/O tunable parameters in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current I/O tunable parameters to their default value.


Changes the next boot I/O tunable parameters to their default values.


Provides options for enabling or disabling Simultaneous Multi-Threading (SMT) and for listing and changing the current SMT settings. SMT mode allows processors on some types of hardware to support multiple thread contexts and to issue instructions for them at the same time. This allows the system to more fully use processor resources that would otherwise be idle.


Displays the following information about each physical processor:

If SMT mode is currently disabled, there will be only one execution thread bound to each physical processor.


Provides options for enabling and disabling Simultaneous Multi-Threading (SMT) on a system where the hardware supports it.


Starts or stops SMT mode. Select "Enabled" to run the system in SMT mode. Select "Disabled" to stop running.

SMT (Simultaneous Multi-Threading) allows the system to multiplex several threads of execution on each physical processor. These threads of execution can be viewed as logical processors. SMT mode is enabled, by default, on systems where the hardware supports it, but you can turn it on or off at any time.


Indicates when to change the SMT mode. Select "Now" to change SMT mode immediately. Select "At subsequent boot" to change SMT mode only when the system is restarted. Select "Now and subsequent boot" to change SMT mode immediately and at the next system restart.


Shows the throughput report for the available adapters on the system.


Displays the statistics for the overall system throughput.


Displays the utilization statistics report for TTY/CPU.


Displays the timestamps along with the I/O statistics report.


Displays the I/O statistics for all available I/O paths.


Displays the utilization statistics for all the disks available on the system.


Displays the Asynchronous I/O statistics on the system. This uses the AIX legacy calls to gather the required data. To retrieve these statistics, Aysnchronous I/O must be enabled on the system.


Displays the Asynchronous I/O statistics. The statistics are collected using POSIX supported calls. To retrieve these statistics, Asynchronous I/O must be enabled on the system.


Displays the queue statistics for the Asynchronous I/O activities on the system. Asynchronous I/O must be enabled on the system for these statistics to be available.


Displays the file system statistics, where the Asynchronous I/O activities are happening. Asynchronous I/O must be enabled on the system for these statistics to be available.


To display the iostat command output using a 132 column format, select "yes". By default, iostat output fits in 80 columns.


To report I/O statistics for a specific drive only, specify the drive here. The default report contains the statistics of all the drives.


Displays the following characteristics and dependencies of the current RAS tunable parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current RAS tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot RAS tunable parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current RAS tunable parameters in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current RAS tunable parameters to their default value.


Changes the next boot RAS tunable parameters to their default values.


Provides options for displaying, modifying, saving, and resetting current and next boot RAS tuning parameters.


Displays the utilization statistics for all the tapes available on the system.


Provides options for managing kernel and network tuning parameters, including the restricted use development parameters. These options allow you to list or change current or next boot values.


Provides options for displaying, modifying, saving, and resetting current and next boot tuning scheduler parameters, including the restricted use development parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot virtual memory tuning parameters, including the restricted use development parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot network tuning parameters, including the restricted use development parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot NFS tuning parameters, including the restricted use development parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot I/O tuning parameters, including the restricted use development parameters.


Provides options for displaying, modifying, saving, and resetting current and next boot RAS tuning parameters, including the restricted use development parameters.


Displays the following characteristics and dependencies of the current scheduler and memory load control tunable parameters, including development parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current scheduler and memory load control tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot scheduler and memory load control tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current scheduler and memory load control tunable parameters, including development parameters, in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current scheduler and memory load control tunable parameters, including development parameters, to their default values.


Changes the next boot scheduler and memory load control tunable parameters, including development parameters, to their default value.


Displays the following characteristics and dependencies of the current virtual memory tunable parameters, including development parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current virtual memory tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot virtual memory tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current virtual memory tunable parameters, including development parameters, in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current virtual memory tunable parameters, including development parameters, to their default value.


Changes the next boot virtual memory tunable parameters, including development parameters, to their default values.


Displays the following characteristics and dependencies of the current network tunable parameters, including development parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current network tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot network tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current network tunable parameters, including development parameters, in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current network tunable parameters, including development parameters, to their default value.


Changes the next boot network tunable parameters, including development parameters, to their default values.


Displays the following characteristics and dependencies of the current NFS tunable parameters, including development parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current NFS tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot NFS tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current NFS tunable parameters, including development parameters, in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current NFS tunable parameters, including development parameters, to their default value.


Changes the next boot NFS tunable parameters, including development parameters, to their default values.


Displays the following characteristics and dependencies of the current I/O tunable parameters, including development parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current I/O tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot I/O tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current I/O tunable parameters, including development parameters, in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current I/O tunable parameters, including development parameters, to their default value.


Changes the next boot I/O tunable parameters, including development parameters, to their default values.


Displays the following characteristics and dependencies of the current RAS tunable parameters, including development parameters:

Current - The value that is currently effective on the system.

Default - The default value set by the tuning command.

Reboot - The value of the parameter changes only after the machine is rebooted.

Minimum - The smallest value accepted by the system.

Maximum - The biggest value accepted by the system.

Unit - The unit of measure for the parameter.

Type - The parameter type, which is any of the following:
Dynamic (D), if the parameter can be changed at any time.
Static (S), if the parameter can never be changed.
Bosboot (B), if the parameter can only be changed by running the bosboot command and rebooting the machine.
Mount (M), if the parameter is only effective for future file system or directory mountings.
Incremental (I), if the parameter can only be incremented during a reboot.


Displays the current RAS tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Displays the next boot RAS tunable parameters, including development parameters. Any null value is understood to be the default value. You can select a parameter and change its value.


Saves the current RAS tunable parameters, including development parameters, in the /etc/tunables/nextboot file for the system to use the next time it is booted.


Changes the current RAS tunable parameters, including development parameters, to their default value.


Changes the next boot RAS tunable parameters, including development parameters, to their default values.