[Perf] Linux/x64: 1 Regression on 8/31/2026 2:56:30 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [5b11923ecac20a8367b4ca60a9b9739479319e9a](https://github.com/dotnet/runtime/commit/5b11923ecac20a8367b4ca60a9b9739479319e9a)
Compare | [ef3efe5e020e412e4f6453781d59443e975010a4](https://github.com/dotnet/runtime/commit/ef3efe5e020e412e4f6453781d59443e975010a4)
Diff | [Diff](https://github.com/dotnet/runtime/compare/5b11923ecac20a8367b4ca60a9b9739479319e9a...ef3efe5e020e412e4f6453781d59443e975010a4)
Configs | CompilationMode:wasm, RunKind:micro

### Regressions in System.Collections.CtorGivenSize<Int32>

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

• [Dictionary - 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.Collections.CtorGivenSize*'
```

### System.Collections.CtorGivenSize<Int32>.Dictionary(Size: 512)

#### 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 linked commit diff and the benchmark source at src/benchmarks/micro/libraries/System.Collections/Create/CtorGivenSize.cs, then reproduce System.Collections.CtorGivenSize with the supplied benchmarks_ci.py command. Compare the baseline and test reports, including the generated IR where available. Done means identifying and addressing or clearly triaging the reported 14% regression.

Written by the indexing model from the issue text.