[Perf] Linux/x64: 3 Regressions on 8/11/2026 11:24:58 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [6597edb0936de18005623b1a17adf29880df60e6](https://github.com/dotnet/runtime/commit/6597edb0936de18005623b1a17adf29880df60e6)
Compare | [19a2d977ed14ff9ab7417519f0257b3b296a82f4](https://github.com/dotnet/runtime/commit/19a2d977ed14ff9ab7417519f0257b3b296a82f4)
Diff | [Diff](https://github.com/dotnet/runtime/compare/6597edb0936de18005623b1a17adf29880df60e6...19a2d977ed14ff9ab7417519f0257b3b296a82f4)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Text.Json.Tests.Utf8JsonReaderCommentsTests

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

• [Utf8JsonReaderCommentParsing - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 190.64 ns | 221.24 ns | 1.16 | 0.10 | 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.Text.Json.Tests.Utf8JsonReaderCommentsTests*'
```

### System.Text.Json.Tests.Utf8JsonReaderCommentsTests.Utf8JsonReaderCommentParsing(CommentHandling: Allow, SegmentSize: 0, TestCase: LongSingleLine)

#### 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 | [6597edb0936de18005623b1a17adf29880df60e6](https://github.com/dotnet/runtime/commit/6597edb0936de18005623b1a17adf29880df60e6)
Compare | [19a2d977ed14ff9ab7417519f0257b3b296a82f4](https://github.com/dotnet/runtime/commit/19a2d977ed14ff9ab7417519f0257b3b296a82f4)
Diff | [Diff](https://github.com/dotnet/runtime/compare/6597edb0936de18005623b1a17adf29880df60e6...19a2d977ed14ff9ab7417519f0257b3b296a82f4)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Numerics.Tests.Perf_BigInteger

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

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

| 802.39 ns | 864.20 ns | 1.08 | 0.01 | 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.Numerics.Tests.Perf_BigInteger*'
```

### System.Numerics.Tests.Perf_BigInteger.ToStringD(numberString: 12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890)

#### 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 | [6597edb0936de18005623b1a17adf29880df60e6](https://github.com/dotnet/runtime/commit/6597edb0936de18005623b1a17adf29880df60e6)
Compare | [19a2d977ed14ff9ab7417519f0257b3b296a82f4](https://github.com/dotnet/runtime/commit/19a2d977ed14ff9ab7417519f0257b3b296a82f4)
Diff | [Diff](https://github.com/dotnet/runtime/compare/6597edb0936de18005623b1a17adf29880df60e6...19a2d977ed14ff9ab7417519f0257b3b296a82f4)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Collections.TryGetValueFalse<SmallClass, SmallClass>

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

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

| 6.40 μs | 6.84 μs | 1.07 | 0.15 | 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.TryGetValueFalse*'
```

### System.Collections.TryGetValueFalse<SmallClass, SmallClass>.ConcurrentDictionary(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 the baseline/compare diff and run the listed benchmarks using performance/scripts/benchmarks_ci.py with the three provided filters. Read the benchmark sources at src/benchmarks/micro/libraries/System.Text.Json/Utf8JsonReader/Utf8JsonReader.Comments.Tests.cs, System.Runtime.Numerics/Perf.BigInteger.cs, and System.Collections/TryGetValue/TryGetValueFalse.cs. Done means explaining and addressing the regressions so the affected measurements no longer exceed the baseline.

Written by the indexing model from the issue text.