[Perf] Linux/x64: 6 Regressions on 8/20/2026 5:39:27 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [7aac3c7ad953aaa23bad1d7867e7a0ec2c4a629c](https://github.com/dotnet/runtime/commit/7aac3c7ad953aaa23bad1d7867e7a0ec2c4a629c)
Compare | [be1c680101458a735200e68a74460919be249315](https://github.com/dotnet/runtime/commit/be1c680101458a735200e68a74460919be249315)
Diff | [Diff](https://github.com/dotnet/runtime/compare/7aac3c7ad953aaa23bad1d7867e7a0ec2c4a629c...be1c680101458a735200e68a74460919be249315)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Reflection.Attributes

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

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

| 214.64 ns | 308.14 ns | 1.44 | 0.12 | False | | |
|

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

| 221.45 ns | 296.93 ns | 1.34 | 0.15 | False | | |
|

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

| 1.22 μs | 1.32 μs | 1.08 | 0.04 | False | | |

![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.Reflection.Attributes*'
```

### System.Reflection.Attributes.IsDefinedClassHit

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Reflection.Attributes.IsDefinedClassHitInherit

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Reflection.Attributes.GetCustomAttributesClassHit

#### 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 | [1f22605f08368b251c9ff73b935a8d7c1df4d174](https://github.com/dotnet/runtime/commit/1f22605f08368b251c9ff73b935a8d7c1df4d174)
Compare | [be1c680101458a735200e68a74460919be249315](https://github.com/dotnet/runtime/commit/be1c680101458a735200e68a74460919be249315)
Diff | [Diff](https://github.com/dotnet/runtime/compare/1f22605f08368b251c9ff73b935a8d7c1df4d174...be1c680101458a735200e68a74460919be249315)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in PerfLabTests.EnumPerf

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

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

| 28.09 ns | 30.06 ns | 1.07 | 0.07 | False | | |
|

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

| 28.58 ns | 30.38 ns | 1.06 | 0.09 | 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 'PerfLabTests.EnumPerf*'
```

### PerfLabTests.EnumPerf.EnumCompareTo(color: Red)

#### ETL Files

#### Histogram

#### JIT Disasms

### PerfLabTests.EnumPerf.EnumEquals

#### 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 | [1f22605f08368b251c9ff73b935a8d7c1df4d174](https://github.com/dotnet/runtime/commit/1f22605f08368b251c9ff73b935a8d7c1df4d174)
Compare | [be1c680101458a735200e68a74460919be249315](https://github.com/dotnet/runtime/commit/be1c680101458a735200e68a74460919be249315)
Diff | [Diff](https://github.com/dotnet/runtime/compare/1f22605f08368b251c9ff73b935a8d7c1df4d174...be1c680101458a735200e68a74460919be249315)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Regressions in System.Collections.CtorFromCollection<Int32>

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

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

| 10.51 μs | 12.89 μs | 1.23 | 0.08 | 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.CtorFromCollection*'
```

### System.Collections.CtorFromCollection<Int32>.ConcurrentQueue(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 benchmark sources src/benchmarks/micro/runtime/System.Reflection/Attributes.cs and src/benchmarks/micro/runtime/perflab/EnumPerf.cs, then run benchmarks_ci.py with the filters shown in the Repro sections. Compare the reported regressions with the linked baseline and compare commits and inspect the performance and test reports. Done means identifying the responsible change and restoring the affected benchmark results.

Written by the indexing model from the issue text.