[Perf] Windows/x86: 2 Improvements on 5/18/2026 5:49:28 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x86
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [db4b5d322efd2cab2287e15200a0b16332b41407](https://github.com/dotnet/runtime/commit/db4b5d322efd2cab2287e15200a0b16332b41407)
Compare | [b540c365da5e5f71a6c0389f5764f363bc59d4a2](https://github.com/dotnet/runtime/commit/b540c365da5e5f71a6c0389f5764f363bc59d4a2)
Diff | [Diff](https://github.com/dotnet/runtime/compare/db4b5d322efd2cab2287e15200a0b16332b41407...b540c365da5e5f71a6c0389f5764f363bc59d4a2)
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]()

| 2.99 ms | 1.72 ms | 0.57 | 0.31 | False | | |
|

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

| 39.71 μs | 31.75 μs | 0.80 | 0.51 | False | | |

![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: 1048576, userBufferSize: 512, options: Asynchronous)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.IO.Tests.Perf_FileStream.ReadAsync(fileSize: 1024, userBufferSize: 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)