[Perf] Linux/x64: 4 Regressions on 5/28/2026 7:26:44 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [50b8d1a7b7bb9c76b4332d44e7093a98ddc8228b](https://github.com/dotnet/runtime/commit/50b8d1a7b7bb9c76b4332d44e7093a98ddc8228b)
Compare | [54cfeb453970e794043c71448a60a39b4fee3a38](https://github.com/dotnet/runtime/commit/54cfeb453970e794043c71448a60a39b4fee3a38)
Diff | [Diff](https://github.com/dotnet/runtime/compare/50b8d1a7b7bb9c76b4332d44e7093a98ddc8228b...54cfeb453970e794043c71448a60a39b4fee3a38)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in System.Globalization.Tests.StringSearch

Benchmark | Baseline | Test | Test/Base | Test Quality | Edge Detector | Baseline IR | Compare IR | IR Ratio
-- | -- | -- | -- | -- | -- | -- | -- | --
|

• [IsPrefix_FirstHalf - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 3.39 μs | 3.72 μs | 1.10 | 0.16 | False | | |
|

• [IsPrefix_FirstHalf - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 3.43 μs | 3.72 μs | 1.08 | 0.12 | False | | |
|

• [IsPrefix_FirstHalf - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 3.26 μs | 3.48 μs | 1.07 | 0.13 | False | | |
|

• [IsPrefix_FirstHalf - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 3.44 μs | 3.63 μs | 1.06 | 0.13 | False | | |

![graph]()
![graph]()
![graph]()
![graph]()
[Test Report]()

### 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.Globalization.Tests.StringSearch*'
```

### System.Globalization.Tests.StringSearch.IsPrefix_FirstHalf(Options: (, IgnoreCase, True))

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Globalization.Tests.StringSearch.IsPrefix_FirstHalf(Options: (, None, True))

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Globalization.Tests.StringSearch.IsPrefix_FirstHalf(Options: (pl-PL, None, False))

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Globalization.Tests.StringSearch.IsPrefix_FirstHalf(Options: (en-US, IgnoreCase, True))

#### 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)