[Perf] Windows/x86: 2 Improvements on 2/27/2026 3:09:53 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [7a5e8fc86df2058a2bc5d5e25cb7309f456befa6](https://github.com/dotnet/runtime/commit/7a5e8fc86df2058a2bc5d5e25cb7309f456befa6)
Compare | [b41bbeab8b775a5058bad74e73a84476bfd8d9a7](https://github.com/dotnet/runtime/commit/b41bbeab8b775a5058bad74e73a84476bfd8d9a7)
Diff | [Diff](https://github.com/dotnet/runtime/compare/7a5e8fc86df2058a2bc5d5e25cb7309f456befa6...b41bbeab8b775a5058bad74e73a84476bfd8d9a7)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Collections.ContainsKeyTrue<String, String>

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

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

| 160.06 μs | 148.67 μs | 0.93 | 0.20 | False | | |

[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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Collections.ContainsKeyTrue*'
```

### System.Collections.ContainsKeyTrue<String, String>.ImmutableSortedDictionary(Size: 512)

#### 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)

---

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [7a5e8fc86df2058a2bc5d5e25cb7309f456befa6](https://github.com/dotnet/runtime/commit/7a5e8fc86df2058a2bc5d5e25cb7309f456befa6)
Compare | [b41bbeab8b775a5058bad74e73a84476bfd8d9a7](https://github.com/dotnet/runtime/commit/b41bbeab8b775a5058bad74e73a84476bfd8d9a7)
Diff | [Diff](https://github.com/dotnet/runtime/compare/7a5e8fc86df2058a2bc5d5e25cb7309f456befa6...b41bbeab8b775a5058bad74e73a84476bfd8d9a7)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.IO.Tests.StreamReaderReadLineTests

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

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

| 97.00 μs | 91.46 μs | 0.94 | 0.02 | False | | |

[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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.IO.Tests.StreamReaderReadLineTests*'
```

### System.IO.Tests.StreamReaderReadLineTests.ReadLine(LineLengthRange: [ 0, 0])

#### 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)