[Perf] Linux/x64: 2 Regressions on 7/5/2026 4:58:39 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [58dfec78ed8de81f527f428f44d095e37fecb401](https://github.com/dotnet/runtime/commit/58dfec78ed8de81f527f428f44d095e37fecb401)
Compare | [ff279bafa8ca2fbf920b605868e9b0a2c0497034](https://github.com/dotnet/runtime/commit/ff279bafa8ca2fbf920b605868e9b0a2c0497034)
Diff | [Diff](https://github.com/dotnet/runtime/compare/58dfec78ed8de81f527f428f44d095e37fecb401...ff279bafa8ca2fbf920b605868e9b0a2c0497034)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in System.Memory.Memory<Char>

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

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

| 20.90 ns | 22.83 ns | 1.09 | 0.11 | 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.Memory.Memory*'
```

### System.Memory.Memory<Char>.Pin(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)

---

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [58dfec78ed8de81f527f428f44d095e37fecb401](https://github.com/dotnet/runtime/commit/58dfec78ed8de81f527f428f44d095e37fecb401)
Compare | [ff279bafa8ca2fbf920b605868e9b0a2c0497034](https://github.com/dotnet/runtime/commit/ff279bafa8ca2fbf920b605868e9b0a2c0497034)
Diff | [Diff](https://github.com/dotnet/runtime/compare/58dfec78ed8de81f527f428f44d095e37fecb401...ff279bafa8ca2fbf920b605868e9b0a2c0497034)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in System.Memory.Memory<Byte>

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

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

| 20.65 ns | 21.91 ns | 1.06 | 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.Memory.Memory*'
```

### System.Memory.Memory<Byte>.Pin(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 src/benchmarks/micro/libraries/System.Memory/Memory.cs#L27-L34 and the benchmarking workflow documentation. Run benchmarks_ci.py with the reported System.Memory.Memory and filters, compare results against the listed baseline and compare commits, and use the linked reports to confirm whether both regressions reproduce. Done means the regression is explained and an appropriate correction or follow-up is identified.

Written by the indexing model from the issue text.