|
|
You can view CPU activity using sar -u on single processor systems:
23:59:44 %usr %sys %wio %idle 23:59:49 4 24 6 66 23:59:54 7 84 0 9 23:59:59 6 70 1 23On systems with an SCO SMP License, use the mpsar -u command to see activity averaged over all the CPUs and cpusar -u to report activity for an individual CPU.Average 5 59 2 32
%usr indicates the percentage of time
that the operating system is executing processes in user mode.
%sys indicates the percentage of time
that the operating system is executing in system mode.
%wio indicates the percentage of time
that the operating system is idle with processes
that could run if they were not waiting for I/O to complete.
%idle indicates the percentage of time
that the operating system is idle with no
runnable processes.
On systems with an SCO SMP License,
a CPU runs a process called idle
if there are no other runnable processes.
On systems using SMP, root can make a CPU inactive using the cpuonoff(ADM) command. The -c option displays the number of active and inactive CPUs:
$ cpuonoff -c cpu 1: active cpu 2: inactive cpu 3: activeThe base processor, which cannot be made inactivate, is always indicated by
cpu 1.
An inactive CPU shows 100% idle
time with the cpusar -u command.
The following sections outline the different process
states and how processes can share the same CPU.