add ability to set custom max time range for benchmarks

benchmarks.go

@@ -7,16 +7,17 @@ import (
 	"time"
 )
 
-var maxTimeRange = time.Duration(15) * time.Minute
+var maxTimeRangeDefault = time.Duration(15) * time.Minute
 
 // Benchmarks is a basic benchmarking middleware collecting and reporting performance metrics
 // It keeps track of the requests speeds and counts in 1s benchData buckets ,limiting the number of buckets
 // to maxTimeRange. User can request the benchmark for any time duration. This is intended to be used
 // for retrieving the benchmark data for the last minute, 5 minutes and up to maxTimeRange.
 type Benchmarks struct {
-	st   time.Time
-	data *list.List
-	lock sync.RWMutex
+	st           time.Time
+	data         *list.List
+	lock         sync.RWMutex
+	maxTimeRange time.Duration
 
 	nowFn func() time.Time // for testing only
 }
@@ -42,13 +43,25 @@ type BenchmarkStats struct {
 // NewBenchmarks creates a new benchmark middleware
 func NewBenchmarks() *Benchmarks {
 	res := &Benchmarks{
-		st:    time.Now(),
-		data:  list.New(),
-		nowFn: time.Now,
+		st:           time.Now(),
+		data:         list.New(),
+		nowFn:        time.Now,
+		maxTimeRange: maxTimeRangeDefault,
 	}
 	return res
 }
 
+// WithTimeRange sets the maximum time range for the benchmark to keep data for.
+// Default is 15 minutes. The increase of this range will change memory utilization as each second of the range
+// kept as benchData aggregate. The default means 15*60 = 900 seconds of data aggregate.
+// Larger range allows for longer time periods to be benchmarked.
+func (b *Benchmarks) WithTimeRange(max time.Duration) *Benchmarks {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+	b.maxTimeRange = max
+	return b
+}
+
 // Handler calculates 1/5/10m request per second and allows to access those values
 func (b *Benchmarks) Handler(next http.Handler) http.Handler {
 
@@ -70,7 +83,7 @@ func (b *Benchmarks) update(reqDuration time.Duration) {
 
 	// keep maxTimeRange in the list, drop the rest
 	for e := b.data.Front(); e != nil; e = e.Next() {
-		if b.data.Front().Value.(benchData).ts.After(b.nowFn().Add(-maxTimeRange)) {
+		if b.data.Front().Value.(benchData).ts.After(b.nowFn().Add(-b.maxTimeRange)) {
 			break
 		}
 		b.data.Remove(b.data.Front())

benchmarks_test.go

@@ -52,6 +52,59 @@ func TestBenchmark_Stats2s(t *testing.T) {
 		MinRespTime: (time.Millisecond * 50).Microseconds(), MaxRespTime: (time.Millisecond * 250).Microseconds()}, res)
 }
 
+func TestBenchmark_WithTimeRange(t *testing.T) {
+
+	nowFn := func(dt time.Time) func() time.Time {
+		return func() time.Time { return dt }
+	}
+
+	{
+		bench := NewBenchmarks().WithTimeRange(time.Minute)
+
+		bench.nowFn = nowFn(time.Date(2018, time.January, 1, 0, 0, 0, 0, time.UTC))
+		bench.update(time.Millisecond * 50)
+		bench.update(time.Millisecond * 150)
+		bench.update(time.Millisecond * 250)
+		bench.update(time.Millisecond * 100)
+
+		bench.nowFn = nowFn(time.Date(2018, time.January, 1, 1, 0, 0, 0, time.UTC)) // 1 hour later
+		bench.update(time.Millisecond * 1000)
+
+		res := bench.Stats(time.Minute)
+		t.Logf("%+v", res)
+		assert.Equal(t, BenchmarkStats{Requests: 1, RequestsSec: 1, AverageRespTime: 1000000,
+			MinRespTime: (time.Millisecond * 1000).Microseconds(), MaxRespTime: (time.Millisecond * 1000).Microseconds()}, res)
+
+		res = bench.Stats(time.Hour)
+		t.Logf("%+v", res)
+		assert.Equal(t, BenchmarkStats{Requests: 1, RequestsSec: 1, AverageRespTime: 1000000,
+			MinRespTime: (time.Millisecond * 1000).Microseconds(), MaxRespTime: (time.Millisecond * 1000).Microseconds()}, res)
+	}
+
+	{
+		bench := NewBenchmarks().WithTimeRange(time.Hour * 2)
+
+		bench.nowFn = nowFn(time.Date(2018, time.January, 1, 0, 0, 0, 0, time.UTC))
+		bench.update(time.Millisecond * 50)
+		bench.update(time.Millisecond * 150)
+		bench.update(time.Millisecond * 250)
+		bench.update(time.Millisecond * 100)
+
+		bench.nowFn = nowFn(time.Date(2018, time.January, 1, 1, 0, 0, 0, time.UTC)) // 1 hour later
+		bench.update(time.Millisecond * 1000)
+
+		res := bench.Stats(time.Minute)
+		t.Logf("%+v", res)
+		assert.Equal(t, BenchmarkStats{Requests: 1, RequestsSec: 1, AverageRespTime: 1000000,
+			MinRespTime: (time.Millisecond * 1000).Microseconds(), MaxRespTime: (time.Millisecond * 1000).Microseconds()}, res)
+
+		res = bench.Stats(time.Hour)
+		t.Logf("%+v", res)
+		assert.Equal(t, BenchmarkStats{Requests: 5, RequestsSec: 0.0013885031935573452, AverageRespTime: 310000,
+			MinRespTime: (time.Millisecond * 50).Microseconds(), MaxRespTime: (time.Millisecond * 1000).Microseconds()}, res)
+	}
+}
+
 func TestBenchmark_Cleanup(t *testing.T) {
 	bench := NewBenchmarks()
 	for i := 0; i < 1000; i++ {