[Perf] Linux/arm64: 3 Improvements on 8/25/2026 10:44:15 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [8baacb006f5615ebd705bdf9de98ca5df7bf1ba1](https://github.com/dotnet/runtime/commit/8baacb006f5615ebd705bdf9de98ca5df7bf1ba1)
Compare | [9f18a550aaa91ecd032ac024b67e03559df9e766](https://github.com/dotnet/runtime/commit/9f18a550aaa91ecd032ac024b67e03559df9e766)
Diff | [Diff](https://github.com/dotnet/runtime/compare/8baacb006f5615ebd705bdf9de98ca5df7bf1ba1...9f18a550aaa91ecd032ac024b67e03559df9e766)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Tests.Perf_Single

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

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

| 112.65 ns | 103.57 ns | 0.92 | 0.12 | False | | |
|

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

| 127.81 ns | 120.39 ns | 0.94 | 0.17 | False | | |
|

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

| 129.61 ns | 122.88 ns | 0.95 | 0.12 | False | | |

![graph]()
![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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Tests.Perf_Single*'
```

### System.Tests.Perf_Single.ToStringWithFormat(value: 3.4028235E+38, format: "E")

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Tests.Perf_Single.ToStringWithCultureInfo(value: -3.4028235E+38, culture: zh)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Tests.Perf_Single.ToStringWithFormat(value: -3.4028235E+38, format: "G")

#### 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 src/benchmarks/micro/libraries/System.Runtime/Perf.Single.cs lines 54-67 and review the linked benchmark reports for the three ARM64 improvements. Run the provided benchmarks_ci.py command to reproduce the measurements; the issue does not define a code change or a clear completion condition beyond investigating the reported results.

Written by the indexing model from the issue text.