CPU info when system has more CPU's (31257)

Where the system that you are diagnosing has two or more CPUs, this control may show a total CPU usage greater than 100%. This value represents the addition of usage percentages across the CPUs, rather than an overall percentage use of CPU resources. But some readings of this control seem to contradict reading from the system.

In Spotlight on Oracle 4.0.4, we calculated Total CPU Usage from the OS command - "vmstat" - on all flavours of UNIX.

We take the sum of user time (column US below) and kernel time (column SY below) to get Total CPU Usage.

So, you would rather check what you are getting from your vmstat command on this host, and compare that result to what's on the SoO homepage.

Example output of vmstat command (from multi cpu AIX box):

$ vmstat 5

System configuration: lcpu=4 mem=3072MB kthr memory page faults cpu

----- ----------- ------------------------ ------------ -----------

r b avm fre re pi po fr sr cy in sy cs US SY id wa

1 2 718344 4786 0 0 0 0 0 0 68 35480 478 26 4 68 1

What SoO would show for this result is 26 + 4 = 30%.

It's also useful to note that SoO averages the CPU number across three samples, so the value on the homepage won't reflect the instantaneous value of VMSTAT (but should be pretty close to it).