[Perf] Linux/arm64: 1 Improvement on 7/8/2026 6:46:25 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [f9a6e2ef41c17130866d7036c5f0cde47e8854af](https://github.com/dotnet/runtime/commit/f9a6e2ef41c17130866d7036c5f0cde47e8854af)
Compare | [2269602f4da6a3a14b3715df41885db28b2e79f8](https://github.com/dotnet/runtime/commit/2269602f4da6a3a14b3715df41885db28b2e79f8)
Diff | [Diff](https://github.com/dotnet/runtime/compare/f9a6e2ef41c17130866d7036c5f0cde47e8854af...2269602f4da6a3a14b3715df41885db28b2e79f8)
Configs | CompilationMode:tiered, R2RType:r2r_interpreter, RunKind:micro

### Improvements in System.Text.Json.Serialization.Tests.WriteJson<BinaryDataPayload>

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

• [SerializeObjectProperty - 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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Text.Json.Serialization.Tests.WriteJson*'
```

### System.Text.Json.Serialization.Tests.WriteJson<BinaryDataPayload>.SerializeObjectProperty(Mode: Reflection)

#### 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.Text.Json/Serializer/WriteJson.cs#L97-L98 and run the provided benchmarks_ci.py command for the WriteJson filter. Compare the arm64 AzureLinux results with the linked baseline and test commits; done means the performance change is explained and any necessary correction is validated by the benchmark.

Written by the indexing model from the issue text.