[Perf] Windows/x64: 1 Improvement on 8/23/2026 3:08:38 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [75cffcef7186a6a0b738f15a98d0b28c6c8e6507](https://github.com/dotnet/runtime/commit/75cffcef7186a6a0b738f15a98d0b28c6c8e6507)
Compare | [868c06ae6fafefd1461e355d1da1dc120b2c0783](https://github.com/dotnet/runtime/commit/868c06ae6fafefd1461e355d1da1dc120b2c0783)
Diff | [Diff](https://github.com/dotnet/runtime/compare/75cffcef7186a6a0b738f15a98d0b28c6c8e6507...868c06ae6fafefd1461e355d1da1dc120b2c0783)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.IO.Tests.Perf_File

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

• [CopyTo - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config 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_File*'
```

### System.IO.Tests.Perf_File.CopyTo(size: 1048576)

#### 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)

Start with the Perf.File.cs benchmark source linked at lines 258-267 and run the provided benchmarks_ci.py command with the System.IO.Tests.Perf_File* filter. Compare the CopyTo result and report against the listed baseline and compare commits. Done means confirming the reported Windows/x64 improvement and documenting the resulting triage or cause.

Written by the indexing model from the issue text.