[Perf] Changes at 12/8/2021 8:10:20 AM

[performanceautofiler]

Run Information

Architecture	x64
OS	Windows 10.0.18362
Baseline	75fe52025a9be974dbf5bfb878f71ed3cad71b8c
Compare	261a2dd6fdb4290bac53be4ea912a7796e510770
Diff	Diff

Regressions in System.IO.Tests.StringReaderReadLineTests

Benchmark	Baseline	Test	Test/Base	Test Quality	Edge Detector	Baseline IR	Compare IR	IR Ratio	Baseline ETL	Compare ETL
ReadLine - Duration of single invocation	71.98 μs	91.76 μs	1.27	0.01	True

Test Report

Repro

git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f net6.0 --filter 'System.IO.Tests.StringReaderReadLineTests*'

Payloads

Baseline
Compare

Histogram

System.IO.Tests.StringReaderReadLineTests.ReadLine(LineLengthRange: [ 1, 1])

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 we could not find enough baseline builds for window checking.
IsChangePoint: Marked as a change because one of 12/8/2021 6:13:42 AM, 1/5/2022 4:19:16 PM falls between 12/6/2021 2:46:54 PM and 1/5/2022 4:19:16 PM.
IsRegressionStdDev: Marked as regression because -91.48350999062747 (T) = (0 -92207.56373796254) / Math.Sqrt((499031.6712495032 / (12)) + (788090.7861426905 / (144))) is less than -1.975488058234161 = MathNet.Numerics.Distributions.StudentT.InvCDF(0, 1, (12) + (144) - 2, .025) and -0.2742538773249618 = (72362.00366251478 - 92207.56373796254) / 72362.00366251478 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 as regression because Edge Detector said so.

Docs

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

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[DrewScoggins]

#60463

[DrewScoggins]

Looks like we are seeing improvements on the longer string inputs, dotnet/perf-autofiling-issues#2670

[stephentoub]

Thanks. Yes, this was expected:
#60463 (comment)
For typical inputs it was a sizeable improvement and only a regression for large files made entirely of really short (e.g. 1 char) lines, which is expected to be rare.