Calculating total ticks consumed in the nomad client

api/nodes.go

@@ -118,10 +118,11 @@ type Node struct {
 
 // HostStats represents resource usage stats of the host running a Nomad client
 type HostStats struct {
-	Memory    *HostMemoryStats
-	CPU       []*HostCPUStats
-	DiskStats []*HostDiskStats
-	Uptime    uint64
+	Memory           *HostMemoryStats
+	CPU              []*HostCPUStats
+	DiskStats        []*HostDiskStats
+	Uptime           uint64
+	CPUTicksConsumed float64
 }
 
 type HostMemoryStats struct {

client/stats/cpu.go

@@ -4,7 +4,7 @@ import (
 	"runtime"
 	"time"
 
-	"github.com/shirou/gopsutil/cpu"
+	shelpers "github.com/hashicorp/nomad/helper/stats"
 )
 
 // CpuStats calculates cpu usage percentage
@@ -23,8 +23,9 @@ func NewCpuStats() *CpuStats {
 		totalCpus: numCpus,
 	}
 
-	// Caluclate the total cpu ticks available across all cores
-	cpuStats.totalTicks()
+	if clkSpeed, err := shelpers.TotalTicksAvailable(); err == nil {
+		cpuStats.clkSpeed = clkSpeed
+	}
 	return cpuStats
 }
 
@@ -52,7 +53,9 @@ func (c *CpuStats) Percent(cpuTime float64) float64 {
 // cpu cores
 func (c *CpuStats) TicksConsumed(percent float64) float64 {
 	if c.clkSpeed == 0.0 {
-		c.totalTicks()
+		if clkSpeed, err := shelpers.TotalTicksAvailable(); err == nil {
+			c.clkSpeed = clkSpeed
+		}
 	}
 	return (percent / 100) * c.clkSpeed
 }
@@ -66,14 +69,3 @@ func (c *CpuStats) calculatePercent(t1, t2 float64, timeDelta int64) float64 {
 	overall_percent := (vDelta / float64(timeDelta)) * 100.0
 	return overall_percent
 }
-
-// totalTicks calculates the total frequency available across all cores
-func (c *CpuStats) totalTicks() {
-	var clkSpeed float64
-	if cpuInfo, err := cpu.Info(); err == nil {
-		for _, cpu := range cpuInfo {
-			clkSpeed += cpu.Mhz
-		}
-	}
-	c.clkSpeed = clkSpeed
-}

client/stats/host.go

@@ -1,21 +1,25 @@
 package stats
 
 import (
+	"runtime"
 	"time"
 
 	"github.com/shirou/gopsutil/cpu"
 	"github.com/shirou/gopsutil/disk"
 	"github.com/shirou/gopsutil/host"
 	"github.com/shirou/gopsutil/mem"
+
+	shelpers "github.com/hashicorp/nomad/helper/stats"
 )
 
 // HostStats represents resource usage stats of the host running a Nomad client
 type HostStats struct {
-	Memory    *MemoryStats
-	CPU       []*CPUStats
-	DiskStats []*DiskStats
-	Uptime    uint64
-	Timestamp int64
+	Memory           *MemoryStats
+	CPU              []*CPUStats
+	DiskStats        []*DiskStats
+	Uptime           uint64
+	Timestamp        int64
+	CPUTicksConsumed float64
 }
 
 // MemoryStats represnts stats related to virtual memory usage
@@ -48,13 +52,23 @@ type DiskStats struct {
 
 // HostStatsCollector collects host resource usage stats
 type HostStatsCollector struct {
+	clkSpeed        float64
+	numCores        int
 	statsCalculator map[string]*HostCpuStatsCalculator
 }
 
 // NewHostStatsCollector returns a HostStatsCollector
 func NewHostStatsCollector() *HostStatsCollector {
+	numCores := runtime.NumCPU()
 	statsCalculator := make(map[string]*HostCpuStatsCalculator)
-	return &HostStatsCollector{statsCalculator: statsCalculator}
+	collector := &HostStatsCollector{
+		statsCalculator: statsCalculator,
+		numCores:        numCores,
+	}
+	if clkSpeed, err := shelpers.TotalTicksAvailable(); err == nil {
+		collector.clkSpeed = clkSpeed
+	}
+	return collector
 }
 
 // Collect collects stats related to resource usage of a host
@@ -70,6 +84,12 @@ func (h *HostStatsCollector) Collect() (*HostStats, error) {
 		hs.Memory = ms
 	}
 
+	ticksConsumed := 0.0
+	if h.clkSpeed == 0.0 {
+		if clkSpeed, err := shelpers.TotalTicksAvailable(); err == nil {
+			h.clkSpeed = clkSpeed
+		}
+	}
 	if cpuStats, err := cpu.Times(true); err == nil {
 		cs := make([]*CPUStats, len(cpuStats))
 		for idx, cpuStat := range cpuStats {
@@ -89,8 +109,10 @@ func (h *HostStatsCollector) Collect() (*HostStats, error) {
 			cs[idx].System = system
 			cs[idx].User = user
 			cs[idx].Total = total
+			ticksConsumed += (total / 100) * h.clkSpeed
 		}
 		hs.CPU = cs
+		hs.CPUTicksConsumed = ticksConsumed
 	}
 
 	if partitions, err := disk.Partitions(false); err == nil {

command/node_status.go

@@ -2,6 +2,7 @@ package command
 
 import (
 	"fmt"
+	"math"
 	"sort"
 	"strconv"
 	"strings"
@@ -405,18 +406,6 @@ func getActualResources(hostStats *api.HostStats, node *api.Node) ([]string, err
 	}
 	var resources []string
 
-	// Calculate cpu usage
-	usedCPUTicks := 0.0
-	if freq, ok := node.Attributes["cpu.frequency"]; ok {
-
-		if clkSpeed, err := strconv.ParseFloat(freq, 64); err == nil {
-			for _, cpu := range hostStats.CPU {
-				usedCPUPercent := (cpu.User + cpu.System)
-				usedCPUTicks += (clkSpeed * usedCPUPercent / 100)
-			}
-		}
-	}
-
 	// calculate disk usage
 	storageDevice := node.Attributes["unique.storage.volume"]
 	var diskUsed, diskSize uint64
@@ -430,7 +419,7 @@ func getActualResources(hostStats *api.HostStats, node *api.Node) ([]string, err
 	resources = make([]string, 2)
 	resources[0] = "CPU|Memory|Disk"
 	resources[1] = fmt.Sprintf("%v/%v|%v/%v|%v/%v",
-		int64(usedCPUTicks),
+		math.Floor(hostStats.CPUTicksConsumed),
 		node.Resources.CPU,
 		humanize.Bytes(hostStats.Memory.Used),
 		humanize.Bytes(hostStats.Memory.Total),