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Splunk Add-on for Unix and Linux: Why does the Percent_CPU_by_Host() macro include %iowait?

Explorer

I use the Splunk Add-on for Unix and Linux.
I use the PercentCPUby_Host() macro.
The macro returns a time-series chart of CPU usage statistics, by host.
However, the CPU usage include %iowait.
I think the %iowait is idle time of CPU. You use CPU usage that is not include iowait.
Is it correct?

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Re: Splunk Add-on for Unix and Linux: Why does the Percent_CPU_by_Host() macro include %iowait?

Communicator

kiyoshi miyake,

%IOWAIT is the amount of time the CPU waited (in an idle state) for an INPUT/OUTPUT device (Hard drive usually) to respond to its request.

Running the 'iostat' command (if on a NIX platform) will yield a lot more information and help you to diagnose an issue with I/O.

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Re: Splunk Add-on for Unix and Linux: Why does the Percent_CPU_by_Host() macro include %iowait?

Explorer

No, I have checked the man page of iostat. I see below.

          %user
                 Show the percentage of CPU utilization that occurred while executing at the user level (application).
          %nice
                 Show the percentage of CPU utilization that occurred while executing at the user level with nice priority.
          %system
                 Show the percentage of CPU utilization that occurred while executing at the system level (kernel).
          %iowait
                 Show the percentage of time that the CPU or CPUs were idle during which the system had an outstanding disk I/O request.
          %steal
                 Show the percentage of time spent in involuntary wait by the virtual CPU or CPUs while the hypervisor was servicing another virtual processor.
          %idle
                 Show the percentage of time that the CPU or CPUs were idle and the system did not have an outstanding disk I/O request.

It mean that %iowait is not CPU utilization, I think.
The CPU utilization = %user + %nice + %system.
Do I misunderstand?

0 Karma
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Re: Splunk Add-on for Unix and Linux: Why does the Percent_CPU_by_Host() macro include %iowait?

Communicator

You are correct, direct CPU utilization is related to what you said:
CPU utilization = %user + %nice + %system

My answer above was simply to elaborate on what you had stated in your question as the description for %IOWAIT.

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Re: Splunk Add-on for Unix and Linux: Why does the Percent_CPU_by_Host() macro include %iowait?

Explorer

The PercentCPUbyHost macro shows percent of CPU Load.
There are another macro Percent
LoadbyHost that shows the result looks like as same as PercentCPUbyHost macro.
Is there CPU
Utilizaton macro???

0 Karma