[Perf] Windows/x64: 4 Regressions on 5/19/2026 2:09:19 AM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [f99b26797b5d3d673f6c37ce3a19fe4117ecded2](https://github.com/dotnet/sdk/commit/f99b26797b5d3d673f6c37ce3a19fe4117ecded2)
Compare | [6fa530d10e7077f6e8ba7620f668d46727fe955d](https://github.com/dotnet/sdk/commit/6fa530d10e7077f6e8ba7620f668d46727fe955d)
Diff | [Diff](https://github.com/dotnet/sdk/compare/f99b26797b5d3d673f6c37ce3a19fe4117ecded2...6fa530d10e7077f6e8ba7620f668d46727fe955d)
Configs | CompilationMode:tiered, RunKind:fsharpmicro

### Regressions in MicroBenchmarks.FSharp.Collections+CollectionsBenchmark

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

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

| 1.48 μs | 1.66 μs | 1.12 | 0.04 | False | | |
|

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

| 130.23 ns | 138.08 ns | 1.06 | 0.03 | False | | |
|

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

| 131.34 ns | 138.38 ns | 1.05 | 0.02 | False | | |
|

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

| 1.55 μs | 1.63 μs | 1.05 | 0.04 | False | | |

![graph]()
![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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'MicroBenchmarks.FSharp.Collections+CollectionsBenchmark*'
```

### MicroBenchmarks.FSharp.Collections+CollectionsBenchmark.ArrayRemoveManyAtBeginning(Length: 10000)

#### ETL Files

#### Histogram

#### JIT Disasms

### MicroBenchmarks.FSharp.Collections+CollectionsBenchmark.ArrayUpdateAtBeginning(Length: 1000)

#### ETL Files

#### Histogram

#### JIT Disasms

### MicroBenchmarks.FSharp.Collections+CollectionsBenchmark.ArrayRemoveManyAtBeginning(Length: 1000)

#### ETL Files

#### Histogram

#### JIT Disasms

### MicroBenchmarks.FSharp.Collections+CollectionsBenchmark.ArrayInsertManyAtEnd(Length: 10000)

#### 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)