Regressions in System.Text.Json.Serialization.Tests.WriteJson<Int32>

[performanceautofiler]

Run Information

Architecture	x64
OS	Windows 10.0.18362
Baseline	315f4ab59adf7eaec815885825c5b0d65fc3ab99
Compare	21a3647f09ca92cbf890129d4e917cbd01a1b374
Diff	Diff

Regressions in System.Text.Json.Serialization.Tests.WriteJson<Int32>

Benchmark	Baseline	Test	Test/Base	Test Quality	Edge Detector	Baseline IR	Compare IR	IR Ratio	Baseline ETL	Compare ETL
SerializeToWriter - Duration of single invocation	53.43 ns	57.39 ns	1.07	0.04	False

Test Report

Repro

git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Text.Json.Serialization.Tests.WriteJson<Int32>*'

Payloads

Baseline
Compare

Histogram

System.Text.Json.Serialization.Tests.WriteJson<Int32>.SerializeToWriter(Mode: Reflection)

Description of detection logic

IsRegressionChecked: Marked as regression because the three check build points were 0.05 greater than the baseline.
IsImprovementBase: Marked as not an improvement because the compare was not 5% less than the baseline, or the value was too small.
IsRegressionBase: Marked as regression because the compare was 5% greater than the baseline, and the value was not too small.
IsRegressionChecked: Marked as regression because the three check build points were 0.05 greater than the baseline.
IsRegressionWindowed: Marked as regression because 57.39010960029418 > 56.44802121461124.
IsChangePoint: Marked as a change because one of 12/5/2022 3:14:07 PM, 12/6/2022 5:44:36 AM falls between 11/27/2022 4:37:47 PM and 12/6/2022 5:44:36 AM.
IsRegressionStdDev: Marked as regression because -15.305777683799269 (T) = (0 -57.15760502498651) / Math.Sqrt((1.5800413402435631 / (44)) + (0.10811675507800535 / (2))) is less than -2.0153675744421933 = MathNet.Numerics.Distributions.StudentT.InvCDF(0, 1, (44) + (2) - 2, .025) and -0.08733531461070963 = (52.566677690819056 - 57.15760502498651) / 52.566677690819056 is less than -0.05.
IsImprovementBase: Marked as not an improvement because the compare was not 5% less than the baseline, or the value was too small.
IsChangeEdgeDetector: Marked not as a regression because Edge Detector said so.

Docs

Profiling workflow for dotnet/runtime repository
Benchmarking workflow for dotnet/runtime repository

[dakersnar]

Probably caused by #78646

[ghost]

Tagging subscribers to this area: @dotnet/area-system-text-json, @gregsdennis
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Run Information

Architecture	x64
OS	Windows 10.0.18362
Baseline	315f4ab59adf7eaec815885825c5b0d65fc3ab99
Compare	21a3647f09ca92cbf890129d4e917cbd01a1b374
Diff	Diff

Regressions in System.Text.Json.Serialization.Tests.WriteJson<Int32>

Benchmark	Baseline	Test	Test/Base	Test Quality	Edge Detector	Baseline IR	Compare IR	IR Ratio	Baseline ETL	Compare ETL
SerializeToWriter - Duration of single invocation	53.43 ns	57.39 ns	1.07	0.04	False

Test Report

Repro

git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Text.Json.Serialization.Tests.WriteJson<Int32>*'

Payloads

Baseline
Compare

Histogram

System.Text.Json.Serialization.Tests.WriteJson<Int32>.SerializeToWriter(Mode: Reflection)

Description of detection logic

IsRegressionChecked: Marked as regression because the three check build points were 0.05 greater than the baseline.
IsImprovementBase: Marked as not an improvement because the compare was not 5% less than the baseline, or the value was too small.
IsRegressionBase: Marked as regression because the compare was 5% greater than the baseline, and the value was not too small.
IsRegressionChecked: Marked as regression because the three check build points were 0.05 greater than the baseline.
IsRegressionWindowed: Marked as regression because 57.39010960029418 > 56.44802121461124.
IsChangePoint: Marked as a change because one of 12/5/2022 3:14:07 PM, 12/6/2022 5:44:36 AM falls between 11/27/2022 4:37:47 PM and 12/6/2022 5:44:36 AM.
IsRegressionStdDev: Marked as regression because -15.305777683799269 (T) = (0 -57.15760502498651) / Math.Sqrt((1.5800413402435631 / (44)) + (0.10811675507800535 / (2))) is less than -2.0153675744421933 = MathNet.Numerics.Distributions.StudentT.InvCDF(0, 1, (44) + (2) - 2, .025) and -0.08733531461070963 = (52.566677690819056 - 57.15760502498651) / 52.566677690819056 is less than -0.05.
IsImprovementBase: Marked as not an improvement because the compare was not 5% less than the baseline, or the value was too small.
IsChangeEdgeDetector: Marked not as a regression because Edge Detector said so.

Docs

Profiling workflow for dotnet/runtime repository
Benchmarking workflow for dotnet/runtime repository

Author:	performanceautofiler[bot]
Assignees:	EgorBo
Labels:	area-System.Text.Json, untriaged
Milestone:	-

[LoopedBard3]

dotnet/perf-autofiling-issues#10388 is a likely dup.

[dakersnar]

More regression data: dotnet/perf-autofiling-issues#10624

[eiriktsarpalis]

The change in #78646 refactors the root-level serialization rootines a bit, which introduces a few additional checks on whether a type is polymorphic. Given that this only appears to impact the allocation-free overloads accepting Utf8JsonWriter for tiny values (int), I'd be inclined to just close this and accept the regression.