[Perf] Linux/x64: 3 Regressions on 9/13/2026 3:54:51 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [b9678dcc0e7bac74a0d6b669b39d1007359b0016](https://github.com/dotnet/runtime/commit/b9678dcc0e7bac74a0d6b669b39d1007359b0016)
Compare | [3c4631e63b1de4308e2965b149992b992c9f5318](https://github.com/dotnet/runtime/commit/3c4631e63b1de4308e2965b149992b992c9f5318)
Diff | [Diff](https://github.com/dotnet/runtime/compare/b9678dcc0e7bac74a0d6b669b39d1007359b0016...3c4631e63b1de4308e2965b149992b992c9f5318)
Configs | CompilationMode:wasm, RunKind:micro

### Regressions in Exceptions.Handling

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

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

| 700.01 ns | 818.30 ns | 1.17 | 0.20 | False | | |
|

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

| 699.76 ns | 797.42 ns | 1.14 | 0.17 | 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 'Exceptions.Handling*'
```

### Exceptions.Handling.MultipleNestedTryCatch_FirstCatches(kind: Software)

#### ETL Files

#### Histogram

#### JIT Disasms

### Exceptions.Handling.ThrowAndCatch(kind: Software)

#### 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 | [b9678dcc0e7bac74a0d6b669b39d1007359b0016](https://github.com/dotnet/runtime/commit/b9678dcc0e7bac74a0d6b669b39d1007359b0016)
Compare | [3c4631e63b1de4308e2965b149992b992c9f5318](https://github.com/dotnet/runtime/commit/3c4631e63b1de4308e2965b149992b992c9f5318)
Diff | [Diff](https://github.com/dotnet/runtime/compare/b9678dcc0e7bac74a0d6b669b39d1007359b0016...3c4631e63b1de4308e2965b149992b992c9f5318)
Configs | CompilationMode:wasm, RunKind:micro

### Regressions in System.IO.MemoryMappedFiles.Tests.Perf_MemoryMappedFile

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

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

| 44.56 μs | 51.03 μs | 1.15 | 0.06 | 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.IO.MemoryMappedFiles.Tests.Perf_MemoryMappedFile*'
```

### System.IO.MemoryMappedFiles.Tests.Perf_MemoryMappedFile.CreateNew(capacity: 10000000)

#### 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 in src/benchmarks/micro/runtime/Exceptions/Handling.cs and src/benchmarks/micro/libraries/System.IO.MemoryMappedFiles/Perf.MemoryMappedFile.cs, then run the listed benchmarks using scripts/benchmarks_ci.py. Compare the reported results with the baseline and commit diff; done means the regressions are reproduced and their cause or disposition is documented.

Written by the indexing model from the issue text.