[BUG]System Guard flow control | CPU thredshold｜ 系统自适应流控｜以CPU作为阈值场景下的取值范围问题

[sunyucheng]

背景：
我在测试使用CPU作为阈值的系统自适应流控方案。
问题：
1、在 func IsValidSystemRule(rule *Rule) error中校验的 cpu取值范围为0.0～1.0。但是在实际测试中发现func getProcessCpuStat() (float64, error)函数的实际返回值大小为0.0～100.0。导致在注册规则时因阈值非法invalid CPU usage, valid range is [0.0, 1.0]而失败。
该处是否应该修改一下cpu的合法性校验范围。

[sunyucheng]

我使用的gosutil是最新的版本v3.21.6,从gosutil的源码看，这里的p.Percent(0)的取值也似乎应该是0.0～100.0,在gosutil中的关键逻辑如下所示

func calculatePercent(t1, t2 *cpu.TimesStat, delta float64, numcpu int) float64 {
	if delta == 0 {
		return 0
	}
	delta_proc := t2.Total() - t1.Total()
	overall_percent := ((delta_proc / delta) * 100) * float64(numcpu)
	return overall_percent
}

https://github.com/shirou/gopsutil/blob/fb83fb22d68f468adf2a01a9ed4963e7d980cfd7/process/process.go#L308

[sunyucheng]

Hi @sczyh30 ,可以给我一些意见么

[binbin0325]

this could be a bug, are you interested in fixing it

[sunyucheng]

this could be a bug, are you interested in fixing it

Certainly

[sunyucheng]

Hi @binbin0325, I have already mentioned PR #540

[erouss]

May I ask why this fix has not passed? Is it not ready to be repaired?

[chenjiaxinatwps]

实际看这个值在多核环境会大于100，还要考虑核数吧
this cpu usage may be > 100, when cpu core > 1. so the cpu num should take into account