[Perf] Linux/x64: 6 Regressions on 7/19/2026 9:49:55 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [4c9e771cbd5e35313cef06c4d7efb55070fd5493](https://github.com/dotnet/runtime/commit/4c9e771cbd5e35313cef06c4d7efb55070fd5493)
Compare | [563abf220847ed66cab58f0d7d166cb264874f40](https://github.com/dotnet/runtime/commit/563abf220847ed66cab58f0d7d166cb264874f40)
Diff | [Diff](https://github.com/dotnet/runtime/compare/4c9e771cbd5e35313cef06c4d7efb55070fd5493...563abf220847ed66cab58f0d7d166cb264874f40)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Buffers.Text.Tests.Utf8ParserTests

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

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

| 52.51 ns | 61.64 ns | 1.17 | 0.06 | False | | |
|

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

| 53.14 ns | 60.96 ns | 1.15 | 0.11 | False | | |
|

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

| 88.88 ns | 99.50 ns | 1.12 | 0.13 | False | | |
|

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

| 88.81 ns | 98.44 ns | 1.11 | 0.08 | False | | |
|

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

| 79.51 ns | 87.42 ns | 1.10 | 0.10 | False | | |
|

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

| 79.11 ns | 86.54 ns | 1.09 | 0.08 | False | | |

![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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Buffers.Text.Tests.Utf8ParserTests*'
```

### System.Buffers.Text.Tests.Utf8ParserTests.TryParseSingle(value: 12345)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Buffers.Text.Tests.Utf8ParserTests.TryParseDouble(value: 12345)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Buffers.Text.Tests.Utf8ParserTests.TryParseDouble(value: 1.7976931348623157e+308)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Buffers.Text.Tests.Utf8ParserTests.TryParseDouble(value: -1.7976931348623157e+308)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Buffers.Text.Tests.Utf8ParserTests.TryParseSingle(value: -3.4028235E+38)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Buffers.Text.Tests.Utf8ParserTests.TryParseSingle(value: 3.4028235E+38)

#### 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.Buffers/Utf8ParserTests.cs and the linked System.Buffers.Text.Tests.Utf8ParserTests report. Run scripts/benchmarks_ci.py with the provided Utf8ParserTests filter, then compare the baseline and compare commits to investigate the six reported regressions. Done means the regression is reproduced and its outcome is documented or resolved against the reported benchmark results.

Written by the indexing model from the issue text.