[Perf] Linux/x64: 3 Regressions on 6/19/2026 7:59:52 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [12d93fcc856b45da44db2a2f0c8ad247bb6a551c](https://github.com/dotnet/runtime/commit/12d93fcc856b45da44db2a2f0c8ad247bb6a551c)
Compare | [95aa263d8387779ef28b1ac89fe186d523bb6c0b](https://github.com/dotnet/runtime/commit/95aa263d8387779ef28b1ac89fe186d523bb6c0b)
Diff | [Diff](https://github.com/dotnet/runtime/compare/12d93fcc856b45da44db2a2f0c8ad247bb6a551c...95aa263d8387779ef28b1ac89fe186d523bb6c0b)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in PerfLabTests.CastingPerf

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

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

| 754.18 ns | 1077.56 ns | 1.43 | 0.35 | 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 'PerfLabTests.CastingPerf*'
```

### PerfLabTests.CastingPerf.CheckArrayIsNonvariantGenericInterfaceNo

#### 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 | [12d93fcc856b45da44db2a2f0c8ad247bb6a551c](https://github.com/dotnet/runtime/commit/12d93fcc856b45da44db2a2f0c8ad247bb6a551c)
Compare | [95aa263d8387779ef28b1ac89fe186d523bb6c0b](https://github.com/dotnet/runtime/commit/95aa263d8387779ef28b1ac89fe186d523bb6c0b)
Diff | [Diff](https://github.com/dotnet/runtime/compare/12d93fcc856b45da44db2a2f0c8ad247bb6a551c...95aa263d8387779ef28b1ac89fe186d523bb6c0b)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in System.Collections.TryGetValueTrue<String, String>

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

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

| 1.58 ms | 1.80 ms | 1.14 | 0.34 | 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.Collections.TryGetValueTrue*'
```

### System.Collections.TryGetValueTrue<String, String>.ConcurrentDictionary(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)

---

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [12d93fcc856b45da44db2a2f0c8ad247bb6a551c](https://github.com/dotnet/runtime/commit/12d93fcc856b45da44db2a2f0c8ad247bb6a551c)
Compare | [95aa263d8387779ef28b1ac89fe186d523bb6c0b](https://github.com/dotnet/runtime/commit/95aa263d8387779ef28b1ac89fe186d523bb6c0b)
Diff | [Diff](https://github.com/dotnet/runtime/compare/12d93fcc856b45da44db2a2f0c8ad247bb6a551c...95aa263d8387779ef28b1ac89fe186d523bb6c0b)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

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

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]()

| 1.55 μs | 1.84 μs | 1.18 | 0.27 | 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.Collections.CtorDefaultSize*'
```

### System.Collections.CtorDefaultSize<String>.Dictionary

#### 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 benchmark sources: src/benchmarks/micro/runtime/perflab/CastingPerf.cs, src/benchmarks/micro/libraries/System.Collections/TryGetValue/TryGetValueTrue.cs, and src/benchmarks/micro/libraries/System.Collections/Create/CtorDefaultSize.cs. Run the provided benchmarks using scripts/benchmarks_ci.py, then compare the results with the baseline and inspect the profiling and benchmarking workflow documentation; done means the reported regressions are understood and addressed.

Written by the indexing model from the issue text.