[Perf] Linux/arm64: 2 Regressions on 3/20/2026 12:54:08 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | ubuntu 22.04
Queue | AmpereUbuntu
Baseline | [b93ce19c8631c0bfdc4188b5eabaa7f6ffb642ef](https://github.com/dotnet/runtime/commit/b93ce19c8631c0bfdc4188b5eabaa7f6ffb642ef)
Compare | [43502e55deaed0a3a9913c10c791ab60c3bc30ee](https://github.com/dotnet/runtime/commit/43502e55deaed0a3a9913c10c791ab60c3bc30ee)
Diff | [Diff](https://github.com/dotnet/runtime/compare/b93ce19c8631c0bfdc4188b5eabaa7f6ffb642ef...43502e55deaed0a3a9913c10c791ab60c3bc30ee)
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
-- | -- | -- | -- | -- | -- | -- | -- | --
|<ul><li>[Count - Duration of single invocation](<https://pvscmdupload.z22.web.core.windows.net/reports/allTestHistory/refs/heads/main_arm64_ubuntu 22.04/System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern%3a%20%22.%7b2%2c4%7d(Tom%7cSawyer%7cHuckleberry%7cFinn)%22%2c%20Options%3a%20None).html>)</li><li>📝 - [Benchmark Source](<https://github.com/dotnet/performance/blob/main/src/benchmarks/micro/libraries/System.Text.RegularExpressions/Perf.Regex.Industry.cs#L242-#L244>)</li><li>[ADX - Test Multi Config Graph](<https://dataexplorer.azure.com/clusters/dotnetperf.westus/databases/PerformanceData?query=H4sIAAAAAAAACl2RTY/TMBCG7yv1Pwy5JBXZJBTo0iBLwNJlESys2gqOlTeZtAbHjuwxTdjuf8fux4XLWB7PvH7mHYkEhJaAwbt4OVjCNlthT9kCN05yM+87g9YKrazPW7LZPZpm7V+xX39WtbNkhvVXFN1fscmutVOU3HMiNKqEKHucpK+ekpVu90u+G9Dsb131W+IDGjPsb4RS4yiF7x0F/RK+aYXj+O3oQnoq3ngRj1VzQhItJpNiMr0sXlxOpqviTVnMytdX2Wx6NZu+nDwvirIoxqdOg532jXGtSSHlxjP5/rPug+Gq2oZ3g43Nt8hrm7dcqHNBpVUjNuHnQfFWVMljfK3bTkgeMO90jXEJMQk0WMcpxAunvghVh6SvNjp+CiCfkG6FJW1ExeVHTvynoG3Q4UZYP20SXGchpMdR2SGmB3oWQnpCZccjPYGx4zEeXeyhM/oXVgRLNAJtCh+ckPXKD7sk3nYp/ODSIQt7O2wGzQKtk/T+Dxq+wdFFnu9ht/WDnBTgmRcn74WFKCI97yvpaowiyHOY915SIugGGiG9llAb0M4vCuyhOQAZVLXfWvC72nJDsPNTQ3IsYGfMvtLStYr9jzsc85YduH0dCZLIYm8feqeH0/UOuXUGW1QUj/8BF89DkcECAAAAAAAAAAAAAAAAAAAAAAAAAAA=>)</li></ul> | 5.01 secs | 5.56 secs | 1.11 | 0.01 | False | | |
|<ul><li>[Count - Duration of single invocation](<https://pvscmdupload.z22.web.core.windows.net/reports/allTestHistory/refs/heads/main_arm64_ubuntu 22.04/System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern%3a%20%22.%7b0%2c2%7d(Tom%7cSawyer%7cHuckleberry%7cFinn)%22%2c%20Options%3a%20None).html>)</li><li>📝 - [Benchmark Source](<https://github.com/dotnet/performance/blob/main/src/benchmarks/micro/libraries/System.Text.RegularExpressions/Perf.Regex.Industry.cs#L242-#L244>)</li><li>[ADX - Test Multi Config Graph](<https://dataexplorer.azure.com/clusters/dotnetperf.westus/databases/PerformanceData?query=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>)</li></ul> | 5.16 secs | 5.51 secs | 1.07 | 0.01 | False | | |

![graph](<https://pvscmdupload.z22.web.core.windows.net/autofilereport/autofilereports/03_26_2026/refs/heads/main_arm64_ubuntu%2022.04_Regression/System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig_001.png>)
![graph](<https://pvscmdupload.z22.web.core.windows.net/autofilereport/autofilereports/03_26_2026/refs/heads/main_arm64_ubuntu%2022.04_Regression/System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig_002.png>)
[Test Report](<https://pvscmdupload.z22.web.core.windows.net/autofilereport/autofilereports/03_26_2026/refs/heads/main_arm64_ubuntu%2022.04_Regression/System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.html>)

### Repro
General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

```cmd
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*'
```

<details>

### System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{2,4}(Tom|Sawyer|Huckleberry|Finn)", Options: None)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{0,2}(Tom|Sawyer|Huckleberry|Finn)", Options: None)

#### ETL Files

#### Histogram

#### JIT Disasms



### Docs

[Profiling workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/profiling-workflow-dotnet-runtime.md)
[Benchmarking workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/benchmarking-workflow-dotnet-runtime.md)

</details>

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

[Perf] Linux/arm64: 2 Regressions on 3/20/2026 12:54:08 AM +00:00 #126156

Run Information

Regressions in System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig

Repro

System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{2,4}(Tom|Sawyer|Huckleberry|Finn)", Options: None)

ETL Files

Histogram

JIT Disasms

System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{0,2}(Tom|Sawyer|Huckleberry|Finn)", Options: None)

ETL Files

Histogram

JIT Disasms

Docs

Metadata

Assignees

Labels

Type

Fields

Projects

Milestone

Relationships

Development

Name	Value
Architecture	arm64
OS	ubuntu 22.04
Queue	AmpereUbuntu
Baseline	b93ce19c8631c0bfdc4188b5eabaa7f6ffb642ef
Compare	43502e55deaed0a3a9913c10c791ab60c3bc30ee
Diff	Diff
Configs	CompilationMode:tiered, RunKind:micro

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	5.01 secs	5.56 secs	1.11	0.01	False
Count - Duration of single invocation 📝 - Benchmark Source ADX - Test Multi Config Graph	5.16 secs	5.51 secs	1.07	0.01	False

[Perf] Linux/arm64: 2 Regressions on 3/20/2026 12:54:08 AM +00:00 #126156

Description

Run Information

Regressions in System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig

Repro

System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{2,4}(Tom|Sawyer|Huckleberry|Finn)", Options: None)

ETL Files

Histogram

JIT Disasms

System.Text.RegularExpressions.Tests.Perf_Regex_Industry_Leipzig.Count(Pattern: ".{0,2}(Tom|Sawyer|Huckleberry|Finn)", Options: None)

ETL Files

Histogram

JIT Disasms

Docs

Metadata

Metadata

Assignees

Labels

Type

Fields

Projects

Milestone

Relationships

Development

Issue actions