[Perf] Linux/x64: 2 Regressions in Regex on 7/11/2024 6:16:28 PM

[performanceautofiler]

Run Information

Name	Value
Architecture	x64
OS	ubuntu 22.04
Queue	ViperUbuntu
Baseline	8ba8249272917366e2382bb4c67a2347d19d2fb6
Compare	cae3aec80d32316026d85228e12a94dd4887d57f
Diff	Diff
Configs	CompilationMode:tiered, RunKind:micro

Regressions in System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig

Benchmark	Baseline	Test	Test/Base	Test Quality	Edge Detector	Baseline IR	Compare IR	IR Ratio
Count - Duration of single invocation 📝 - Benchmark Source ADX - Test Multi Config Graph	45.62 ms	48.73 ms	1.07	0.03	False
Count - Duration of single invocation 📝 - Benchmark Source ADX - Test Multi Config Graph	44.85 ms	48.43 ms	1.08	0.03	False

Test Report

Repro

General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

git clone https://github.com/dotnet/performance.git
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig*'

System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{2,4}(Tom|Sawyer|Huckleberry|Finn)", Options: NonBacktracking)

ETL Files

Histogram

JIT Disasms

System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{0,2}(Tom|Sawyer|Huckleberry|Finn)", Options: NonBacktracking)

ETL Files

Histogram

JIT Disasms

Docs

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

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[DrewScoggins]

Seems related to this pr, #102655.

[veanes]

My guess is that perf regression by 7%-8% on this (Twain) benchmark is related to a tradeoff in search heuristics
that on the other hand boosted other benchmarks, but I asked @ieviev to take a closer look into this too.

[LoopedBard3]

Related Regressions:

• [Perf] Windows/x64: 8 Regressions on 7/11/2024 6:16:28 PM perf-autofiling-issues#38297
• [Perf] Linux/x64: 4 Regressions on 7/12/2024 7:02:19 PM perf-autofiling-issues#38275
• [Perf] Windows/arm64: 1 Regression on 7/11/2024 4:22:20 PM perf-autofiling-issues#38531
• [Perf] Linux/arm64: 4 Regressions on 7/11/2024 4:22:20 PM perf-autofiling-issues#38485