[Perf] Windows/x64: 2 Regressions on 9/4/2026 2:43:47 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | x64
OS | Windows 10.0.22631
Queue | ViperWindows
Baseline | [134de00ac5934568c582a35322ae16a228db430d](https://github.com/dotnet/runtime/commit/134de00ac5934568c582a35322ae16a228db430d)
Compare | [7e807becb8c6b1917dac0565c674ade7947a8bec](https://github.com/dotnet/runtime/commit/7e807becb8c6b1917dac0565c674ade7947a8bec)
Diff | [Diff](https://github.com/dotnet/runtime/compare/134de00ac5934568c582a35322ae16a228db430d...7e807becb8c6b1917dac0565c674ade7947a8bec)
Configs | CompilationMode:tiered, RunKind:micro

### Regressions in Microsoft.Extensions.Caching.Memory.Tests.MemoryCacheTests

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

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

| 20.22 μs | 21.94 μs | 1.09 | 0.09 | False | | |
|

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

| 13.58 ns | 14.72 ns | 1.08 | 0.02 | 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
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'Microsoft.Extensions.Caching.Memory.Tests.MemoryCacheTests*'
```

### Microsoft.Extensions.Caching.Memory.Tests.MemoryCacheTests.AddThenRemove_ExpirationTokens

#### ETL Files

#### Histogram

#### JIT Disasms

### Microsoft.Extensions.Caching.Memory.Tests.MemoryCacheTests.CreateEntry

#### 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 dotnet/performance/src/benchmarks/micro/libraries/Microsoft.Extensions.Caching.Memory/MemoryCacheTests.cs at the CreateEntry and AddThenRemove_ExpirationTokens benchmarks, then run the provided benchmarks_ci.py command. Compare the baseline and compare commits and inspect the linked performance reports. Done means the Windows/x64 regressions are explained and a validated fix or triage outcome is recorded.

Written by the indexing model from the issue text.