metrics: replace gosigar with gopsutil (#21041)

* replace gosigar with gopsutil

* removed check for whether GOOS is openbsd

* removed accidental import of runtime

* potential fix for difference in units between gosig and gopsutil

* fixed lint error

* remove multiplication factor

* uses cpu.ClocksPerSec as the multiplication factor

* changed dependency from shirou to renaynay (#20)

* updated dep

* switching back from using renaynay fork to using upstream as PRs were merged on upstream

* removed empty line

* optimized imports

* tidied go mod

metrics/cpu_enabled.go

@@ -18,14 +18,22 @@
 
 package metrics
 
-import "github.com/elastic/gosigar"
+import (
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/shirou/gopsutil/cpu"
+)
 
 // ReadCPUStats retrieves the current CPU stats.
 func ReadCPUStats(stats *CPUStats) {
-	global := gosigar.Cpu{}
-	global.Get()
-
-	stats.GlobalTime = int64(global.User + global.Nice + global.Sys)
-	stats.GlobalWait = int64(global.Wait)
+	// passing false to request all cpu times
+	timeStats, err := cpu.Times(false)
+	if err != nil {
+		log.Error("Could not read cpu stats", "err", err)
+		return
+	}
+	// requesting all cpu times will always return an array with only one time stats entry
+	timeStat := timeStats[0]
+	stats.GlobalTime = int64((timeStat.User + timeStat.Nice + timeStat.System) * cpu.ClocksPerSec)
+	stats.GlobalWait = int64((timeStat.Iowait) * cpu.ClocksPerSec)
 	stats.LocalTime = getProcessCPUTime()
 }