[Perf] Linux/x64: 2 Regressions on 7/15/2026 11:45:31 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [051c1fd3c13fea8c1e60b68d9c7f63c3173e5593](https://github.com/dotnet/runtime/commit/051c1fd3c13fea8c1e60b68d9c7f63c3173e5593)
Compare | [1594ad1e1b5313c3ece119ced82b0a7ed2be7fbb](https://github.com/dotnet/runtime/commit/1594ad1e1b5313c3ece119ced82b0a7ed2be7fbb)
Diff | [Diff](https://github.com/dotnet/runtime/compare/051c1fd3c13fea8c1e60b68d9c7f63c3173e5593...1594ad1e1b5313c3ece119ced82b0a7ed2be7fbb)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.IO.Tests.Perf_Path

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

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

| 198.01 ns | 210.86 ns | 1.06 | 0.09 | False | | |

![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.IO.Tests.Perf_Path*'
```

### System.IO.Tests.Perf_Path.GetRandomFileName

#### 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 | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [051c1fd3c13fea8c1e60b68d9c7f63c3173e5593](https://github.com/dotnet/runtime/commit/051c1fd3c13fea8c1e60b68d9c7f63c3173e5593)
Compare | [1594ad1e1b5313c3ece119ced82b0a7ed2be7fbb](https://github.com/dotnet/runtime/commit/1594ad1e1b5313c3ece119ced82b0a7ed2be7fbb)
Diff | [Diff](https://github.com/dotnet/runtime/compare/051c1fd3c13fea8c1e60b68d9c7f63c3173e5593...1594ad1e1b5313c3ece119ced82b0a7ed2be7fbb)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Tests.Perf_Guid

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

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

| 188.27 ns | 198.28 ns | 1.05 | 0.07 | False | | |

![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.Tests.Perf_Guid*'
```

### System.Tests.Perf_Guid.NewGuid

#### 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 benchmark sources in performance/src/benchmarks/micro/libraries/System.Runtime.Extensions/Perf.Path.cs and performance/src/benchmarks/micro/libraries/System.Runtime/Perf.Guid.cs, then run the provided benchmarks_ci.py filters. Compare the reported baseline and test results for GetRandomFileName and NewGuid, use the linked reports and commit diff to investigate the regressions, and confirm completion with benchmark results showing the regressions are understood and addressed.

Written by the indexing model from the issue text.