Windows setting CPU Percents on cpu.TimeStat object

[dadgar]

This should probably be a different struct as the other methods will accept it and behave incorrectly. Also it causes upstream bugs on code that relies on it not being a percent.

https://github.com/shirou/gopsutil/blob/master/cpu/cpu_windows.go#L140

[shirou]

Sorry, currently I don't have time to investigate this. What struct should we use? Could you send a PR?

[dadgar]

The CPU package doesn't really have an appropriate struct. I would at the very minimum add documentation stating the different behavior on the Windows platform.

[dadgar]

What makes it even more confusing is that cpu.Times(false) is in ticks but cpu.Times(true) is in percents.

Ticks: https://github.com/shirou/gopsutil/blob/master/cpu/cpu_windows.go#L52-L76
Percents: https://github.com/shirou/gopsutil/blob/master/cpu/cpu_windows.go#L131

[marcospedreiro]

I was taking a look at this today and was doing some experimentation here

I started using the WMI Code generator tool to see what we could get, and saw that the current class we're querying (win32_perfformatteddata_counters_processorinformation) does return percentage values.

I used the WMI code generator tool to see if there were any other classes that might get us the CPU time values and I saw win32_perfrawdata_counters_processorinformation. From the linked documentation, they are stated to return identical values, except the latter has a few extra fields.

However querying my windows computer for win32_perfrawdata_counters_processorinformation returned different values that were not percentages. I did a quick swap out to use this new class and got the following results utilizing the following code:

package main

import (
	"fmt"

	"github.com/marcospedreiro/gopsutil/cpu"
)

func main() {
	fmt.Println("[windows] cpu.Times(false)")
	t, err := cpu.Times(false)
	if err != nil {
		fmt.Println(err)
		return
	}
	for _, ct := range t {
		fmt.Println(ct)
	}

	fmt.Println("[windows] cpu.Times(true)")
	t, err = cpu.Times(true)
	if err != nil {
		fmt.Println(err)
		return
	}
	for _, ctf := range t {
		fmt.Println(ctf)
	}

	return
}

Currently when I run this on master I get the following on my windows computer:

[windows] cpu.Times(false)
{"cpu":"cpu-total","user":68496.5,"system":12999.8,"idle":126170.3,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
[windows] cpu.Times(true)
{"cpu":"0,0","user":0.0,"system":0.0,"idle":100.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,1","user":0.0,"system":12.0,"idle":92.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,2","user":0.0,"system":0.0,"idle":100.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,3","user":0.0,"system":6.0,"idle":99.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,4","user":6.0,"system":0.0,"idle":99.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,5","user":0.0,"system":6.0,"idle":99.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}

With my commit that I linked above I get the following:

[windows] cpu.Times(false)
{"cpu":"cpu-total","user":69030.2,"system":13576.2,"idle":155644.0,"nice":0.0,"iowait":0.0,"irq":0.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
[windows] cpu.Times(true)
{"cpu":"0,5","user":111033750000.0,"system":19630000000.0,"idle":266419843750.0,"nice":0.0,"iowait":0.0,"irq":196250000.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,4","user":112372968750.0,"system":21042968750.0,"idle":263667656250.0,"nice":0.0,"iowait":0.0,"irq":167031250.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,3","user":111817812500.0,"system":21075781250.0,"idle":264189843750.0,"nice":0.0,"iowait":0.0,"irq":182343750.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,2","user":121851093750.0,"system":16515312500.0,"idle":258717187500.0,"nice":0.0,"iowait":0.0,"irq":147968750.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,1","user":125105781250.0,"system":22633437500.0,"idle":249344375000.0,"nice":0.0,"iowait":0.0,"irq":199062500.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}
{"cpu":"0,0","user":108120156250.0,"system":34864062500.0,"idle":254101875000.0,"nice":0.0,"iowait":0.0,"irq":4299218750.0,"softirq":0.0,"steal":0.0,"guest":0.0,"guestNice":0.0,"stolen":0.0}

It appears that the win32_perfrawdata_counters_processorinformation may be giving us cpu time data as opposed to percentages, but what I've found in terms of documentation so far has not been helpful, not to mention that we are off by a couple orders of magnitude from the cpu-total values.

If we sum the user time values for each core:

111033750000.0 + 112372968750.0 + 111817812500.0 + 121851093750.0 + 125105781250.0 + 108120156250.0

we get

690301562500 which is the same value as the cpu total 69030.2 except larger by a factor of 10,000,000, which is the number of clock ticks per second on windows

I'm happy to clean up my commit and submit a PR if we feel this is the correct approach to go with.

[Lomanic]

Fixed by #611.