[Perf] Linux/x64: 3 Improvements on 5/19/2026 3:17:56 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [286dc1501f7bc16b2b170ec68d70bb755476d4ea](https://github.com/dotnet/runtime/commit/286dc1501f7bc16b2b170ec68d70bb755476d4ea)
Compare | [c6a8e4caf07c58141038ca47aedc61ff39d33d96](https://github.com/dotnet/runtime/commit/c6a8e4caf07c58141038ca47aedc61ff39d33d96)
Diff | [Diff](https://github.com/dotnet/runtime/compare/286dc1501f7bc16b2b170ec68d70bb755476d4ea...c6a8e4caf07c58141038ca47aedc61ff39d33d96)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Memory.Span<Byte>

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

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

| 14.37 ns | 5.42 ns | 0.38 | 0.33 | False | | |
|

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

| 20.29 ns | 15.78 ns | 0.78 | 0.62 | False | | |

![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.Memory.Span*'
```

### System.Memory.Span<Byte>.Fill(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Memory.Span<Byte>.CopyToOverlap(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 | [286dc1501f7bc16b2b170ec68d70bb755476d4ea](https://github.com/dotnet/runtime/commit/286dc1501f7bc16b2b170ec68d70bb755476d4ea)
Compare | [c6a8e4caf07c58141038ca47aedc61ff39d33d96](https://github.com/dotnet/runtime/commit/c6a8e4caf07c58141038ca47aedc61ff39d33d96)
Diff | [Diff](https://github.com/dotnet/runtime/compare/286dc1501f7bc16b2b170ec68d70bb755476d4ea...c6a8e4caf07c58141038ca47aedc61ff39d33d96)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Collections.CtorDefaultSize<Int32>

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

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

| 1132.69 ns | 652.99 ns | 0.58 | 0.67 | 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.CtorDefaultSize*'
```

### System.Collections.CtorDefaultSize<Int32>.ConcurrentBag

#### 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)