Merge pull request #164 from prometheus/extensibility/futureproof/values

Refresh SampleValue to 64-bit floating point.

model/data.proto

@@ -50,8 +50,8 @@ message SampleKey {
 
 message SampleValueSeries {
   message Value {
-    optional int64 timestamp = 1;
+    optional int64  timestamp = 1;
-    optional float value     = 2;
+    optional double value     = 2;
   }
   repeated Value value = 1;
 }

model/metric.go

@@ -15,6 +15,7 @@ package model
 
 import (
 	"bytes"
+	"code.google.com/p/goprotobuf/proto"
 	"fmt"
 	"sort"
 	"time"
@@ -70,10 +71,12 @@ func (l LabelSet) String() string {
 type Metric map[LabelName]LabelValue
 
 // A SampleValue is a representation of a value for a given sample at a given
-// time.  It is presently float32 due to that being the representation that
+// time.
-// Protocol Buffers provide of floats in Go.  This is a smell and should be
+type SampleValue float64
-// remedied down the road.
+
-type SampleValue float32
+func (s SampleValue) ToDTO() *float64 {
+	return proto.Float64(float64(s))
+}
 
 func (v SampleValue) MarshalJSON() ([]byte, error) {
 	return []byte(fmt.Sprintf("\"%f\"", v)), nil

retrieval/format/processor0_0_1_test.go

@@ -59,14 +59,14 @@ func testProcessor001Process(t test.Tester) {
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.010000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "zed"},
-						Value:  0.04598141,
+						Value:  0.0459814091918713,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.010000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "bar"},
-						Value:  78.485634,
+						Value:  78.48563317257356,
 					},
 				},
 				{
@@ -80,14 +80,14 @@ func testProcessor001Process(t test.Tester) {
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.050000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "zed"},
-						Value:  0.04598141,
+						Value:  0.0459814091918713,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.050000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "bar"},
-						Value:  78.485634,
+						Value:  78.48563317257356,
 					},
 				},
 				{
@@ -101,63 +101,63 @@ func testProcessor001Process(t test.Tester) {
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.500000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "zed"},
-						Value:  0.61204565,
+						Value:  0.6120456642749681,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.500000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "bar"},
-						Value:  97.317986,
+						Value:  97.31798360385088,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.500000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "foo"},
-						Value:  84.63044,
+						Value:  84.63044031436561,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.900000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "zed"},
-						Value:  1.3559151,
+						Value:  1.355915069887731,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.900000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "bar"},
-						Value:  109.89202,
+						Value:  109.89202084295582,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.900000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "foo"},
-						Value:  160.21101,
+						Value:  160.21100853053224,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.990000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "zed"},
-						Value:  1.7727332,
+						Value:  1.772733213161236,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.990000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "bar"},
-						Value:  109.99626,
+						Value:  109.99626121011262,
 					},
 				},
 				{
 					Sample: model.Sample{
 
 						Metric: model.Metric{"percentile": "0.990000", model.MetricNameLabel: "rpc_latency_microseconds", "service": "foo"},
-						Value:  172.49829,
+						Value:  172.49828748957728,
 					},
 				},
 			},

rules/rules_test.go

@@ -235,7 +235,7 @@ var expressionTests = []struct {
 	}, {
 		// Rates should transform per-interval deltas to per-second rates.
 		expr:           "rate(http_requests{group='canary',instance='1',job='app-server'}[10m])",
-		output:         []string{"http_requests{group='canary',instance='1',job='app-server'} => 0.26666668 @[%v]"},
+		output:         []string{"http_requests{group='canary',instance='1',job='app-server'} => 0.26666666666666666 @[%v]"},
 		fullRanges:     1,
 		intervalRanges: 0,
 	}, {

storage/metric/curator_test.go

@@ -40,7 +40,7 @@ type (
 
 	sample struct {
 		time  time.Time
-		value float32
+		value float64
 	}
 
 	sampleGroup struct {
@@ -90,7 +90,7 @@ func (s sampleGroup) Get() (key, value coding.Encoder) {
 	for _, value := range s.values {
 		series.Value = append(series.Value, &dto.SampleValueSeries_Value{
 			Timestamp: proto.Int64(value.time.Unix()),
-			Value:     proto.Float32(float32(value.value)),
+			Value:     proto.Float64(value.value),
 		})
 	}
 

storage/metric/leveldb.go

@@ -619,7 +619,7 @@ func (l *LevelDBMetricPersistence) AppendSamples(samples model.Samples) (err err
 			for _, sample := range chunk {
 				value.Value = append(value.Value, &dto.SampleValueSeries_Value{
 					Timestamp: proto.Int64(sample.Timestamp.Unix()),
-					Value:     proto.Float32(float32(sample.Value)),
+					Value:     sample.Value.ToDTO(),
 				})
 			}
 

storage/metric/rule_integration_test.go

@@ -26,7 +26,7 @@ func GetValueAtTimeTests(persistenceMaker func() (MetricPersistence, test.Closer
 		month time.Month
 		day   int
 		hour  int
-		value float32
+		value float64
 	}
 
 	type input struct {
@@ -358,7 +358,7 @@ func GetBoundaryValuesTests(persistenceMaker func() (MetricPersistence, test.Clo
 		month time.Month
 		day   int
 		hour  int
-		value float32
+		value float64
 	}
 
 	type input struct {
@@ -672,7 +672,7 @@ func GetRangeValuesTests(persistenceMaker func() (MetricPersistence, test.Closer
 		month time.Month
 		day   int
 		hour  int
-		value float32
+		value float64
 	}
 
 	type input struct {
@@ -691,7 +691,7 @@ func GetRangeValuesTests(persistenceMaker func() (MetricPersistence, test.Closer
 		month time.Month
 		day   int
 		hour  int
-		value float32
+		value model.SampleValue
 	}
 
 	type behavior struct {

storage/metric/stochastic_test.go

@@ -233,10 +233,12 @@ func levelDBGetRangeValues(l *LevelDBMetricPersistence, fp model.Fingerprint, i
 			return nil, err
 		}
 
-		samples = append(samples, model.SamplePair{
+		for _, value := range retrievedValue.Value {
-			Value:     model.SampleValue(*retrievedValue.Value[0].Value),
+			samples = append(samples, model.SamplePair{
-			Timestamp: indexable.DecodeTime(retrievedKey.Timestamp),
+				Value:     model.SampleValue(*value.Value),
-		})
+				Timestamp: time.Unix(*value.Timestamp, 0),
+			})
+		}
 	}
 
 	return