[Perf] Linux/arm64: 2 Improvements on 5/28/2026 7:07:22 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | ubuntu 22.04
Queue | AmpereUbuntu
Baseline | [15b34f616c22708246df76232450a9c4fdb2a2e4](https://github.com/dotnet/runtime/commit/15b34f616c22708246df76232450a9c4fdb2a2e4)
Compare | [760c770a3c5427b1811a978f1252e2ed2bc9d110](https://github.com/dotnet/runtime/commit/760c770a3c5427b1811a978f1252e2ed2bc9d110)
Diff | [Diff](https://github.com/dotnet/runtime/compare/15b34f616c22708246df76232450a9c4fdb2a2e4...760c770a3c5427b1811a978f1252e2ed2bc9d110)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Collections.CreateAddAndClear<String>

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

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

| 295.70 μs | 231.13 μs | 0.78 | 0.45 | False | | |
|

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

| 2.97 μs | 2.53 μs | 0.85 | 0.37 | False | | |

![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.CreateAddAndClear*'
```

### System.Collections.CreateAddAndClear<String>.ImmutableDictionary(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CreateAddAndClear<String>.Span(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)