[Perf] Linux/x64: 2 Regressions on 8/22/2026 2:29:58 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [129ada6e62fb997068c4151f69ecb3e39fb6f4be](https://github.com/dotnet/runtime/commit/129ada6e62fb997068c4151f69ecb3e39fb6f4be)
Compare | [75cffcef7186a6a0b738f15a98d0b28c6c8e6507](https://github.com/dotnet/runtime/commit/75cffcef7186a6a0b738f15a98d0b28c6c8e6507)
Diff | [Diff](https://github.com/dotnet/runtime/compare/129ada6e62fb997068c4151f69ecb3e39fb6f4be...75cffcef7186a6a0b738f15a98d0b28c6c8e6507)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in Microsoft.Extensions.DependencyInjection.GetServiceIEnumerable

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

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

| 2.08 μs | 3.20 μs | 1.54 | 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 'Microsoft.Extensions.DependencyInjection.GetServiceIEnumerable*'
```

### Microsoft.Extensions.DependencyInjection.GetServiceIEnumerable.Singleton

#### 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 | [76c60b960a2daa412c44a5061abf66f3286f6a92](https://github.com/dotnet/runtime/commit/76c60b960a2daa412c44a5061abf66f3286f6a92)
Compare | [75cffcef7186a6a0b738f15a98d0b28c6c8e6507](https://github.com/dotnet/runtime/commit/75cffcef7186a6a0b738f15a98d0b28c6c8e6507)
Diff | [Diff](https://github.com/dotnet/runtime/compare/76c60b960a2daa412c44a5061abf66f3286f6a92...75cffcef7186a6a0b738f15a98d0b28c6c8e6507)
Configs | CompilationMode:wasm, RunKind:micro, RuntimeType:coreclr

### Regressions in System.Collections.Perf_LengthBucketsFrozenDictionary

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

• [ToFrozenDictionary - Duration of single invocation]()
• [ADX - Test Multi Config Graph]()

| 19.10 μs | 21.48 μs | 1.12 | 0.30 | 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.Perf_LengthBucketsFrozenDictionary*'
```

### System.Collections.Perf_LengthBucketsFrozenDictionary.ToFrozenDictionary(Count: 10, ItemsPerBucket: 5)

#### 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 source at src/benchmarks/micro/libraries/Microsoft.Extensions.DependencyInjection/IEnumerableGetServiceBenchmark.cs and the two linked test reports. Run the provided benchmarks_ci.py filters, then compare the baseline and test commits and inspect the profiling and benchmarking workflow documentation. Done means the causes of both regressions are identified and the affected benchmark results no longer regress.

Written by the indexing model from the issue text.