Procstat input plugin should use the same timestamp in all metrics in…

… the same Gather() cycle. (#8658)

(cherry picked from commit 70d2b1f)

plugins/inputs/procstat/procstat.go

@@ -118,6 +118,8 @@ func (p *Procstat) Gather(acc telegraf.Accumulator) error {
 	}
 
 	pids, tags, err := p.findPids(acc)
+	now := time.Now()
+
 	if err != nil {
 		fields := map[string]interface{}{
 			"pid_count":   0,
@@ -128,7 +130,7 @@ func (p *Procstat) Gather(acc telegraf.Accumulator) error {
 			"pid_finder": p.PidFinder,
 			"result":     "lookup_error",
 		}
-		acc.AddFields("procstat_lookup", fields, tags)
+		acc.AddFields("procstat_lookup", fields, tags, now)
 		return err
 	}
 
@@ -140,7 +142,7 @@ func (p *Procstat) Gather(acc telegraf.Accumulator) error {
 	p.procs = procs
 
 	for _, proc := range p.procs {
-		p.addMetric(proc, acc)
+		p.addMetric(proc, acc, now)
 	}
 
 	fields := map[string]interface{}{
@@ -150,13 +152,13 @@ func (p *Procstat) Gather(acc telegraf.Accumulator) error {
 	}
 	tags["pid_finder"] = p.PidFinder
 	tags["result"] = "success"
-	acc.AddFields("procstat_lookup", fields, tags)
+	acc.AddFields("procstat_lookup", fields, tags, now)
 
 	return nil
 }
 
 // Add metrics a single Process
-func (p *Procstat) addMetric(proc Process, acc telegraf.Accumulator) {
+func (p *Procstat) addMetric(proc Process, acc telegraf.Accumulator, t time.Time) {
 	var prefix string
 	if p.Prefix != "" {
 		prefix = p.Prefix + "_"
@@ -309,7 +311,7 @@ func (p *Procstat) addMetric(proc Process, acc telegraf.Accumulator) {
 		}
 	}
 
-	acc.AddFields("procstat", fields, proc.Tags())
+	acc.AddFields("procstat", fields, proc.Tags(), t)
 }
 
 // Update monitored Processes

plugins/inputs/procstat/procstat_test.go

@@ -402,3 +402,20 @@ func TestProcstatLookupMetric(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, len(p.procs)+1, len(acc.Metrics))
 }
+
+func TestGather_SameTimestamps(t *testing.T) {
+	var acc testutil.Accumulator
+	pidfile := "/path/to/pidfile"
+
+	p := Procstat{
+		PidFile:         pidfile,
+		createPIDFinder: pidFinder([]PID{pid}, nil),
+		createProcess:   newTestProc,
+	}
+	require.NoError(t, acc.GatherError(p.Gather))
+
+	procstat, _ := acc.Get("procstat")
+	procstat_lookup, _ := acc.Get("procstat_lookup")
+
+	require.Equal(t, procstat.Time, procstat_lookup.Time)
+}