Skip to content

Reset scale of exponential histogram #6557

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 14 commits into
base: main
Choose a base branch
from
+21 −10
Open

Reset scale of exponential histogram #6557

Show file tree
Hide file tree
Changes from 4 commits
Commits
Show all changes
14 commits
Select commit Hold shift + click to select a range
d048664
fix reset scale if delta for exponential histogram
hannahhaering Oct 1, 2025
aae33d9
Merge branch 'open-telemetry:main' into exponential-histogram-reset-s…
hannahhaering Oct 1, 2025
d1520cb
test if scale has been reset
hannahhaering Oct 1, 2025
51ce77d
Merge branch 'exponential-histogram-reset-scale' of https://github.co…
hannahhaering Oct 1, 2025
c738bb9
Merge branch 'main' into exponential-histogram-reset-scale
hannahhaering Oct 2, 2025
76337c4
added changelog entry
hannahhaering Oct 2, 2025
e4d35ec
Merge branch 'main' into exponential-histogram-reset-scale
hannahhaering Oct 6, 2025
bc0d165
improve exponential histogram reset
hannahhaering Oct 7, 2025
91a56dc
Update src/OpenTelemetry/Metrics/MetricPoint/MetricPoint.cs
hannahhaering Oct 7, 2025
c8ce84d
Update src/OpenTelemetry/Metrics/MetricPoint/MetricPoint.cs
hannahhaering Oct 7, 2025
a8010d9
Update test/OpenTelemetry.Tests/Metrics/AggregatorTests.cs
hannahhaering Oct 7, 2025
84c6276
Update test/OpenTelemetry.Tests/Metrics/AggregatorTests.cs
hannahhaering Oct 7, 2025
72560e1
fix arguments and string interpolation in test
hannahhaering Oct 7, 2025
093f6e4
Merge branch 'main' into exponential-histogram-reset-scale
hannahhaering Oct 7, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 7 additions & 3 deletions src/OpenTelemetry/Metrics/MetricPoint/Base2ExponentialBucketHistogram.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -197,10 +197,14 @@ public void Record(double value)
Debug.Assert(n == 0, "Increment should always succeed after scale down.");
}

internal void Reset()
internal void Reset(bool isDelta)
{
// TODO: Determine if this is sufficient for delta temporality.
// I'm not sure we should be resetting the scale.
if (isDelta)
{
this.Scale = Metric.DefaultExponentialHistogramMaxScale;
this.RunningSum = 0;
}

this.ZeroCount = 0;
this.PositiveBuckets.Reset();
this.NegativeBuckets.Reset();
Expand Down
6 changes: 2 additions & 4 deletions src/OpenTelemetry/Metrics/MetricPoint/MetricPoint.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -820,8 +820,7 @@ internal void TakeSnapshot(bool outputDelta)
if (outputDelta)
{
this.runningValue.AsLong = 0;
histogram.RunningSum = 0;
histogram.Reset();
histogram.Reset(outputDelta);
}

this.MetricPointStatus = MetricPointStatus.NoCollectPending;
Expand All @@ -848,8 +847,7 @@ internal void TakeSnapshot(bool outputDelta)
if (outputDelta)
{
this.runningValue.AsLong = 0;
histogram.RunningSum = 0;
histogram.Reset();
histogram.Reset(outputDelta);
histogram.RunningMin = double.PositiveInfinity;
histogram.RunningMax = double.NegativeInfinity;
}
Expand Down
7 changes: 6 additions & 1 deletion test/OpenTelemetry.Tests/Metrics/AggregatorTests.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -352,10 +352,12 @@ internal void ExponentialHistogramTests(AggregationType aggregationType, Aggrega
var count = metricPoint.GetHistogramCount();
var sum = metricPoint.GetHistogramSum();
var hasMinMax = metricPoint.TryGetHistogramMinMaxValues(out var min, out var max);
var firstScale = metricPoint.GetExponentialHistogramData().Scale;

AssertExponentialBucketsAreCorrect(expectedHistogram, metricPoint.GetExponentialHistogramData());
Assert.Equal(50, sum);
Assert.Equal(6, count);
Assert.True(firstScale <= Metric.DefaultExponentialHistogramMaxScale);

if (aggregationType == AggregationType.Base2ExponentialHistogramWithMinMax)
{
Expand All @@ -373,12 +375,14 @@ internal void ExponentialHistogramTests(AggregationType aggregationType, Aggrega
count = metricPoint.GetHistogramCount();
sum = metricPoint.GetHistogramSum();
hasMinMax = metricPoint.TryGetHistogramMinMaxValues(out min, out max);
var secondScale = metricPoint.GetExponentialHistogramData().Scale;

if (aggregationTemporality == AggregationTemporality.Cumulative)
{
AssertExponentialBucketsAreCorrect(expectedHistogram, metricPoint.GetExponentialHistogramData());
Assert.Equal(50, sum);
Assert.Equal(6, count);
Assert.Equal(firstScale, secondScale);

if (aggregationType == AggregationType.Base2ExponentialHistogramWithMinMax)
{
Expand All @@ -393,10 +397,11 @@ internal void ExponentialHistogramTests(AggregationType aggregationType, Aggrega
}
else
{
expectedHistogram.Reset();
expectedHistogram.Reset(true);
AssertExponentialBucketsAreCorrect(expectedHistogram, metricPoint.GetExponentialHistogramData());
Assert.Equal(0, sum);
Assert.Equal(0, count);
Assert.Equal(Metric.DefaultExponentialHistogramMaxScale, secondScale);

if (aggregationType == AggregationType.Base2ExponentialHistogramWithMinMax)
{
Expand Down
Loading