[Perf] Linux/x64: 3 Improvements on 7/14/2026 2:58:00 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [8a5301832157c4740b8c85ee25086762b29af531](https://github.com/dotnet/runtime/commit/8a5301832157c4740b8c85ee25086762b29af531)
Compare | [1baa904ac12c971494469fc724fb3b9f7126716d](https://github.com/dotnet/runtime/commit/1baa904ac12c971494469fc724fb3b9f7126716d)
Diff | [Diff](https://github.com/dotnet/runtime/compare/8a5301832157c4740b8c85ee25086762b29af531...1baa904ac12c971494469fc724fb3b9f7126716d)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

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

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

• [OrderedDictionary - Duration of single invocation]()
• [ADX - Test Multi Config Graph]()

| 29.00 ns | 23.87 ns | 0.82 | 0.12 | False | | |
|

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

| 22.33 ns | 19.68 ns | 0.88 | 0.14 | 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.CtorDefaultSize*'
```

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

#### ETL Files

#### Histogram

#### JIT Disasms

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

#### 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 | [8a5301832157c4740b8c85ee25086762b29af531](https://github.com/dotnet/runtime/commit/8a5301832157c4740b8c85ee25086762b29af531)
Compare | [1baa904ac12c971494469fc724fb3b9f7126716d](https://github.com/dotnet/runtime/commit/1baa904ac12c971494469fc724fb3b9f7126716d)
Diff | [Diff](https://github.com/dotnet/runtime/compare/8a5301832157c4740b8c85ee25086762b29af531...1baa904ac12c971494469fc724fb3b9f7126716d)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

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

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

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

| 1.41 μs | 1.18 μs | 0.83 | 0.06 | 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.IndexerSet*'
```

### System.Collections.IndexerSet<String>.Array(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 scripts/benchmarks_ci.py and the reported benchmark sources: src/benchmarks/micro/libraries/System.Collections/Create/CtorDefaultSize.cs and src/benchmarks/micro/libraries/System.Collections/Indexer/IndexerSet.cs. Run the supplied filters, then compare the linked baseline and test reports for the WebAssembly configuration. Done means the performance changes are reproduced and explained, with any required follow-up recorded.

Written by the indexing model from the issue text.