Performance measurement and tuning for BSD 4.3 system managers

Thie following discusses AIX® device attributes and performance measurement and tuning.

All devices on AIX have attributes associated with them. To view device attributes, enter:

lsattr -E -l devicename

Any attributes with the value True can be modified with the command:

chdev -l devicename -a attr=value

Attention: Changing device parameters incorrectly can damage your system.

By default, the maximum number of processes per user is 40. The default value might be too low for users who have many windows open simultaneously. The following command can be used to change the value systemwide:

hdev -l sys0 -a maxuproc=100

This example changes the maximum number to 100. The new value is set once the system has restarted.

To view the current setting of this and other system attributes, type:

lsattr -E -l sys0

The maxmbuf attribute is not currently supported by the mbuf services.

AIX supports the vmstat and iostat commands, but not the systat command or load averages. For more information about these commands, see vmstat and iostat.