[Perf] Linux/arm64: 11 Improvements on 6/25/2026 12:43:10 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [9c1fdaea7e4595785db31a5a219f66fb7d2a4ec1](https://github.com/dotnet/runtime/commit/9c1fdaea7e4595785db31a5a219f66fb7d2a4ec1)
Compare | [818cfd5edcda78ac3eb201af392fd301ab9ad46b](https://github.com/dotnet/runtime/commit/818cfd5edcda78ac3eb201af392fd301ab9ad46b)
Diff | [Diff](https://github.com/dotnet/runtime/compare/9c1fdaea7e4595785db31a5a219f66fb7d2a4ec1...818cfd5edcda78ac3eb201af392fd301ab9ad46b)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Text.Json.Tests.Perf_Strings

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

• [WriteStringsUtf16 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 105.74 ms | 27.68 ms | 0.26 | 0.22 | False | | |
|

• [WriteStringsUtf16 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 104.70 ms | 37.81 ms | 0.36 | 0.20 | False | | |
|

• [WriteStringsUtf8 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 113.56 ms | 41.15 ms | 0.36 | 0.23 | False | | |
|

• [WriteStringsUtf8 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 106.00 ms | 39.13 ms | 0.37 | 0.19 | False | | |
|

• [WriteStringsUtf8 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 113.80 ms | 42.86 ms | 0.38 | 0.22 | False | | |
|

• [WriteStringsUtf8 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 105.44 ms | 41.68 ms | 0.40 | 0.24 | False | | |
|

• [WriteStringsUtf16 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 105.19 ms | 42.21 ms | 0.40 | 0.30 | False | | |
|

• [WriteStringsUtf16 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 105.92 ms | 42.79 ms | 0.40 | 0.20 | False | | |
|

• [WriteStringsUtf16 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 12.84 ms | 10.66 ms | 0.83 | 0.25 | False | | |
|

• [WriteStringsUtf16 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 12.88 ms | 12.03 ms | 0.93 | 0.23 | False | | |
|

• [WriteStringsUtf8 - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 11.41 ms | 10.69 ms | 0.94 | 0.26 | False | | |

![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![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.Text.Json.Tests.Perf_Strings*'
```

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf16(Formatted: True, SkipValidation: False, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf16(Formatted: False, SkipValidation: True, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf8(Formatted: False, SkipValidation: False, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf8(Formatted: False, SkipValidation: True, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf8(Formatted: True, SkipValidation: True, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf8(Formatted: True, SkipValidation: False, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf16(Formatted: False, SkipValidation: False, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf16(Formatted: True, SkipValidation: True, Escaped: AllEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf16(Formatted: False, SkipValidation: True, Escaped: OneEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf16(Formatted: False, SkipValidation: False, Escaped: OneEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf8(Formatted: True, SkipValidation: False, Escaped: OneEscaped)

#### 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 source at src/benchmarks/micro/libraries/System.Text.Json/Utf8JsonWriter/Perf.Strings.cs, lines 82-116, and compare the baseline and test reports for the listed ARM64 configurations. Determine whether the observed improvements require follow-up in the runtime; the issue does not define a specific code change or completion criterion.

Written by the indexing model from the issue text.