Extended metrics with Serve stats

Signed-off-by: Plamen Petrov <plamb0brt@gmail.com>

metrics/metrics_test.go

@@ -67,3 +67,12 @@ func TestLoadSnapshotStats(t *testing.T) {
 
 	PrintLoadSnapshotStats(s1, s2)
 }
+
+func TestServeStats(t *testing.T) {
+	s1 := NewServeStat()
+	s1.GetResponse = 25
+	s1.RetireOld = 10
+	require.Equal(t, int64(35), s1.Total(), "Total is incorrect")
+
+	PrintServeStats(s1)
+}

metrics/serveStat.go

@@ -0,0 +1,85 @@
+// MIT License
+//
+// Copyright (c) 2020 Plamen Petrov
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package metrics
+
+import (
+	"fmt"
+
+	"gonum.org/v1/gonum/stat"
+)
+
+// NewServeStat Creates a new ServeStat
+func NewServeStat() *ServeStat {
+	s := new(ServeStat)
+	return s
+}
+
+// Total Calculates the total time it took to Serve
+func (s *ServeStat) Total() int64 {
+	return s.AddInstance + s.GetResponse + s.RetireOld
+}
+
+// PrintTotal Prints the total time to Serve
+func (s *ServeStat) PrintTotal() {
+	fmt.Printf("Serve total: %d us\n", s.Total())
+}
+
+// PrintAll Prints a breakdown of the time it took to Serve
+func (s *ServeStat) PrintAll() {
+	fmt.Printf("Serve Stats  \tus\n")
+	fmt.Printf("GetImage     \t%d\n", s.AddInstance)
+	fmt.Printf("FcCreateVM   \t%d\n", s.GetResponse)
+	fmt.Printf("NewContainer \t%d\n", s.RetireOld)
+	fmt.Printf("Total        \t%d\n", s.Total())
+}
+
+// PrintServeStats prints the mean and
+// standard deviation of each component of
+// ServeStat statistics
+func PrintServeStats(startVMstats ...*ServeStat) {
+	addInstances := make([]float64, len(startVMstats))
+	getResponses := make([]float64, len(startVMstats))
+	retireOlds := make([]float64, len(startVMstats))
+	totals := make([]float64, len(startVMstats))
+
+	for i, s := range startVMstats {
+		addInstances[i] = float64(s.AddInstance)
+		getResponses[i] = float64(s.GetResponse)
+		retireOlds[i] = float64(s.RetireOld)
+		totals[i] = float64(s.Total())
+	}
+
+	var (
+		mean float64
+		std  float64
+	)
+	fmt.Printf("Serve Stats   \tMean(us)\tStdDev(us)\n")
+	mean, std = stat.MeanStdDev(addInstances, nil)
+	fmt.Printf("AddInstance   \t%12.2f\t%12.2f\n", mean, std)
+	mean, std = stat.MeanStdDev(getResponses, nil)
+	fmt.Printf("GetResponse   \t%12.2f\t%12.2f\n", mean, std)
+	mean, std = stat.MeanStdDev(retireOlds, nil)
+	fmt.Printf("RetireOld     \t%12.2f\t%12.2f\n", mean, std)
+	mean, std = stat.MeanStdDev(totals, nil)
+	fmt.Printf("Total         \t%12.2f\t%12.2f\n", mean, std)
+}

metrics/types.go

@@ -43,3 +43,10 @@ type StartVMStat struct {
 	TaskWait     int64
 	TaskStart    int64
 }
+
+// ServeStat Serve Stats
+type ServeStat struct {
+	AddInstance int64
+	GetResponse int64
+	RetireOld   int64
+}