[Perf] Windows/x86: 4 Improvements on 3/21/2026 3:23:56 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [1a7eb82a99a7f677460a45a18138b6b7d32f080d](https://github.com/dotnet/runtime/commit/1a7eb82a99a7f677460a45a18138b6b7d32f080d)
Compare | [9ddca1d12b9183a8c3e1f374ea845b0056e6f30e](https://github.com/dotnet/runtime/commit/9ddca1d12b9183a8c3e1f374ea845b0056e6f30e)
Diff | [Diff](https://github.com/dotnet/runtime/compare/1a7eb82a99a7f677460a45a18138b6b7d32f080d...9ddca1d12b9183a8c3e1f374ea845b0056e6f30e)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.IO.Tests.Perf_FileStream

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

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

| 16.24 μs | 12.80 μs | 0.79 | 0.10 | False | | |
|

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

| 18.32 ns | 15.07 ns | 0.82 | 0.05 | False | | |
|

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

| 781.40 μs | 415.07 μs | 0.53 | 0.33 | False | | |
|

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

| 23.12 μs | 19.21 μs | 0.83 | 0.02 | 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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.IO.Tests.Perf_FileStream*'
```

### System.IO.Tests.Perf_FileStream.Read(fileSize: 1024, userBufferSize: 1024, options: None)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.IO.Tests.Perf_FileStream.GetLength(options: Read)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.IO.Tests.Perf_FileStream.Read_NoBuffering(fileSize: 1048576, userBufferSize: 16384, options: Asynchronous)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.IO.Tests.Perf_FileStream.SeekForward(fileSize: 1024, options: Asynchronous)

#### 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)