[Perf] Linux/x64: 1 Regression on 7/23/2026 4:52:54 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [dc3757e67b2d6eb7d6db7e052574a02c3d445432](https://github.com/dotnet/runtime/commit/dc3757e67b2d6eb7d6db7e052574a02c3d445432)
Compare | [3e64752d437bc3429276c0cd019f30e6d4088d1f](https://github.com/dotnet/runtime/commit/3e64752d437bc3429276c0cd019f30e6d4088d1f)
Diff | [Diff](https://github.com/dotnet/runtime/compare/dc3757e67b2d6eb7d6db7e052574a02c3d445432...3e64752d437bc3429276c0cd019f30e6d4088d1f)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in System.Diagnostics.Perf_Activity

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

• [EnumerateActivityTagObjectsSmall - 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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Diagnostics.Perf_Activity*'
```

### System.Diagnostics.Perf_Activity.EnumerateActivityTagObjectsSmall

#### 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 System.Diagnostics.Perf_Activity benchmark source at src/benchmarks/micro/libraries/System.Diagnostics/Perf_Activity.cs#L121-L127 and reproduce it using the benchmarks_ci.py command in the issue. Compare the listed baseline and test commits, then use the linked test report and profiling workflow to identify the regression; done means the cause is understood and the benchmark no longer shows the reported regression.

Written by the indexing model from the issue text.