[Perf] Linux/x64: 1 Regression on 9/9/2026 5:28:54 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [bd7f7404b0b4ad43847b20e0cb9f16a9e13cd4f8](https://github.com/dotnet/runtime/commit/bd7f7404b0b4ad43847b20e0cb9f16a9e13cd4f8)
Compare | [bd707a42fb3b58bb6053a13ae09c76fb72d794d7](https://github.com/dotnet/runtime/commit/bd707a42fb3b58bb6053a13ae09c76fb72d794d7)
Diff | [Diff](https://github.com/dotnet/runtime/compare/bd7f7404b0b4ad43847b20e0cb9f16a9e13cd4f8...bd707a42fb3b58bb6053a13ae09c76fb72d794d7)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in System.Collections.CtorFromCollection<String>

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

• [List - 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.CtorFromCollection*'
```

### System.Collections.CtorFromCollection<String>.List(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 benchmark source at src/benchmarks/micro/libraries/System.Collections/Create/CtorFromCollection.cs#L42-L43 and run the provided benchmarks_ci.py command. Compare the baseline and compare commits, then use the linked test report and profiling workflow docs to identify the regression. Done means the reported System.Collections.CtorFromCollection.List(Size: 512) performance regression is resolved and the benchmark no longer reproduces it.

Written by the indexing model from the issue text.