Function TestGaugeVecConcurrency

prometheus/gauge_test.go:99–162

(t *testing.T)

}

func TestGaugeVecConcurrency(t *testing.T) {
	it := func(n uint32) bool {
		mutations := int(n % 10000)
		concLevel := int(n%15 + 1)
		vecLength := int(n%5 + 1)

		var start, end sync.WaitGroup
		start.Add(1)
		end.Add(concLevel)

		sStreams := make([]chan float64, vecLength)
		results := make([]chan float64, vecLength)
		done := make(chan struct{})

		for i := 0; i < vecLength; i++ {
			sStreams[i] = make(chan float64, mutations*concLevel)
			results[i] = make(chan float64)
			go listenGaugeStream(sStreams[i], results[i], done)
		}

		go func() {
			end.Wait()
			close(done)
		}()

		gge := NewGaugeVec(
			GaugeOpts{
				Name: "test_gauge",
				Help: "no help can be found here",
			},
			[]string{"label"},
		)
		for i := 0; i < concLevel; i++ {
			vals := make([]float64, mutations)
			pick := make([]int, mutations)
			for j := 0; j < mutations; j++ {
				vals[j] = rand.Float64() - 0.5
				pick[j] = rand.Intn(vecLength)
			}

			go func(vals []float64) {
				start.Wait()
				for i, v := range vals {
					sStreams[pick[i]] <- v
					gge.WithLabelValues(string('A' + rune(pick[i]))).Add(v)
				}
				end.Done()
			}(vals)
		}
		start.Done()

		for i := range sStreams {
			if expected, got := <-results[i], math.Float64frombits(gge.WithLabelValues(string('A'+rune(i))).(*gauge).valBits); math.Abs(expected-got) > 0.000001 {
				t.Fatalf("expected approx. %f, got %f", expected, got)
				return false
			}
		}
		return true