[Perf] Linux/x64: 21 Improvements on 9/7/2026 9:35:50 AM +00:00

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#79,296 opened on Sep 10, 2026 2 comments 0 reactions 0 assignees View on GitHub

arch-wasm arch-x64 branch-refs/heads/main chrome-update compilationmode-wasm kind-micro Look Again os-linux perf-improvement PGO runkind-micro

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Forks: 8
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Description

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [570fcdab16c5b674bb59007f4faa705671d69cc2](https://github.com/dotnet/runtime/commit/570fcdab16c5b674bb59007f4faa705671d69cc2)
Compare | [294fe754ccc3db80640c7e34018d97cfac834f51](https://github.com/dotnet/runtime/commit/294fe754ccc3db80640c7e34018d97cfac834f51)
Diff | [Diff](https://github.com/dotnet/runtime/compare/570fcdab16c5b674bb59007f4faa705671d69cc2...294fe754ccc3db80640c7e34018d97cfac834f51)
Configs | CompilationMode:wasm, RunKind:micro

### Improvements in System.Collections.CopyTo<String>

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

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

| 1.65 μs | 1.54 μs | 0.94 | 0.02 | False | | |
|

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

| 1.67 μs | 1.57 μs | 0.94 | 0.01 | False | | |
|

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

| 1.65 μs | 1.55 μs | 0.94 | 0.03 | False | | |
|

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

| 1.66 μs | 1.57 μs | 0.94 | 0.04 | False | | |
|

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

| 1.66 μs | 1.57 μs | 0.94 | 0.00 | False | | |

![graph]()
![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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Collections.CopyTo*'
```

### System.Collections.CopyTo<String>.ReadOnlySpan(Size: 2048)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CopyTo<String>.Memory(Size: 2048)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CopyTo<String>.Span(Size: 2048)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CopyTo<String>.List(Size: 2048)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Collections.CopyTo<String>.ReadOnlyMemory(Size: 2048)

#### 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

### Improvements in System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>

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

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

| 1.76 μs | 1.34 μs | 0.76 | 0.05 | False | | |
|

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

| 35.72 μs | 30.63 μs | 0.86 | 0.02 | False | | |
|

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

| 1.39 μs | 1.28 μs | 0.92 | 0.03 | False | | |
|

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

| 31.79 μs | 29.46 μs | 0.93 | 0.02 | 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
python3 .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives*'
```

### System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>.Pow_ScalarExponent(BufferLength: 128)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>.Pow_ScalarExponent(BufferLength: 3079)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>.Pow_ScalarBase(BufferLength: 128)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Numerics.Tensors.Tests.Perf_FloatingPointTensorPrimitives<Single>.Pow_ScalarBase(BufferLength: 3079)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.MathBenchmarks.Single

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

[Exp10M1 - Duration of single invocation]()
📝 - [Benchmark Source]()
[ADX - Test Multi Config Graph]()

| 103.33 μs | 65.27 μs | 0.63 | 0.04 | False | | |
|

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

| 62.55 μs | 45.89 μs | 0.73 | 0.18 | False | | |
|

[Exp10 - Duration of single invocation]()
📝 - [Benchmark Source]()
[ADX - Test Multi Config Graph]()

| 86.56 μs | 64.24 μs | 0.74 | 0.08 | 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.MathBenchmarks.Single*'
```

### System.MathBenchmarks.Single.Exp10M1

#### ETL Files

#### Histogram

#### JIT Disasms

### System.MathBenchmarks.Single.Atan

#### ETL Files

#### Histogram

#### JIT Disasms

### System.MathBenchmarks.Single.Exp10

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.MathBenchmarks.Double

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

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

| 88.23 μs | 68.96 μs | 0.78 | 0.07 | False | | |
|

[Log10 - Duration of single invocation]()
📝 - [Benchmark Source]()
[ADX - Test Multi Config Graph]()

| 82.06 μs | 67.63 μs | 0.82 | 0.27 | False | | |
|

[Exp2 - Duration of single invocation]()
📝 - [Benchmark Source]()
[ADX - Test Multi Config Graph]()

| 117.82 μs | 99.63 μs | 0.85 | 0.10 | 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.MathBenchmarks.Double*'
```

### System.MathBenchmarks.Double.Acos

#### ETL Files

#### Histogram

#### JIT Disasms

### System.MathBenchmarks.Double.Log10

#### ETL Files

#### Histogram

#### JIT Disasms

### System.MathBenchmarks.Double.Exp2

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.Collections.CreateAddAndClear<String>

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

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

| 5.64 μs | 4.97 μs | 0.88 | 0.10 | 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.CreateAddAndClear*'
```

### System.Collections.CreateAddAndClear<String>.Span(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in PerfLabTests.CastingPerf2.CastingPerf

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

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

| 1102.26 μs | 961.32 μs | 0.87 | 0.14 | 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 'PerfLabTests.CastingPerf2.CastingPerf*'
```

### PerfLabTests.CastingPerf2.CastingPerf.FooObjCastIfIsa

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.Diagnostics.Tracing.Perf_EventListener

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

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

| 22.55 ns | 19.53 ns | 0.87 | 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.Diagnostics.Tracing.Perf_EventListener*'
```

### System.Diagnostics.Tracing.Perf_EventListener.WriteEvent_IntParams

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in PerfLabTests.DelegatePerf

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

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

| 54.85 ms | 50.39 ms | 0.92 | 0.00 | 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 'PerfLabTests.DelegatePerf*'
```

### PerfLabTests.DelegatePerf.MulticastDelegateCombineInvoke

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [570fcdab16c5b674bb59007f4faa705671d69cc2](https://github.com/dotnet/runtime/commit/570fcdab16c5b674bb59007f4faa705671d69cc2)
Compare | [fb98b574c9c5bcea55f33dbad31c418c8815ce8e](https://github.com/dotnet/runtime/commit/fb98b574c9c5bcea55f33dbad31c418c8815ce8e)
Diff | [Diff](https://github.com/dotnet/runtime/compare/570fcdab16c5b674bb59007f4faa705671d69cc2...fb98b574c9c5bcea55f33dbad31c418c8815ce8e)
Configs | CompilationMode:wasm, RunKind:micro

### Improvements in PerfLabTests.CastingPerf

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

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

| 1065.43 μs | 799.25 μs | 0.75 | 0.09 | 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 'PerfLabTests.CastingPerf*'
```

### PerfLabTests.CastingPerf.FooObjCastIfIsa

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.Collections.IndexerSet<String>

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

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

| 4.82 μs | 4.53 μs | 0.94 | 0.16 | 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.IndexerSet*'
```

### System.Collections.IndexerSet<String>.Array(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

Contributor guide

No contributing guide indexed for this repository

Research direction

Start with the benchmark sources in performance/src/benchmarks/micro/libraries/System.Collections/CopyTo.cs and System.Numerics.Tensors/Perf_FloatingPointTensorPrimitives.cs, then run the provided benchmarks_ci.py command. Compare the baseline and test reports for the listed improvements and determine whether the observed change has an actionable runtime cause or needs further triage.

Written by the indexing model from the issue text.

Assessment

Tech stack: csharp, wasm
Domain: performance, testing
Issue type: Bug
Difficulty: 4/5
Estimated time: 3-5 days
Activity status: Active
Clarity: Needs clarification
Newbie friendliness: 35/100

[Perf] Linux/x64: 21 Improvements on 9/7/2026 9:35:50 AM +00:00

Description

Contributor guide

Research direction

Assessment

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