[Perf] Linux/x64: 5 Improvements on 8/4/2026 8:53:30 PM +00:00

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#77,866 opened on Aug 13, 2026 1 comment 0 reactions 0 assignees View on GitHub

aot-true arch-wasm arch-x64 bdn-update branch-refs/heads/main compilationmode-wasm kind-micro Look Again os-linux perf-improvement runkind-micro untriaged wasm-aot

Dominant language: No language data
Stars: 10
Forks: 8
PR merge metrics: PR metrics pending

Description

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [2dd5330804f9d4f49599d82c90a67892d4dd8af0](https://github.com/dotnet/runtime/commit/2dd5330804f9d4f49599d82c90a67892d4dd8af0)
Compare | [173e6b40e02cd1652102c09e07bd4cf7320b3d4d](https://github.com/dotnet/runtime/commit/173e6b40e02cd1652102c09e07bd4cf7320b3d4d)
Diff | [Diff](https://github.com/dotnet/runtime/compare/2dd5330804f9d4f49599d82c90a67892d4dd8af0...173e6b40e02cd1652102c09e07bd4cf7320b3d4d)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

### Improvements in System.Collections.CtorFromCollection<Int32>

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

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

| 84.92 μs | 27.39 μs | 0.32 | 0.13 | 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.CtorFromCollection*'
```

### System.Collections.CtorFromCollection<Int32>.ImmutableList(Size: 512)

#### 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.Collections.IterateForEach<Int32>

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

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

| 92.52 μs | 81.48 μs | 0.88 | 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 'System.Collections.IterateForEach*'
```

### System.Collections.IterateForEach<Int32>.ImmutableSortedDictionary(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.Text.Json.Tests.Perf_Strings

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

[WriteStringsUtf8 - Duration of single invocation]()
📝 - [Benchmark Source]()
[ADX - Test Multi Config Graph]()

| 9.03 ms | 8.29 ms | 0.92 | 0.05 | 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.Text.Json.Tests.Perf_Strings*'
```

### System.Text.Json.Tests.Perf_Strings.WriteStringsUtf8(Formatted: True, SkipValidation: False, Escaped: NoneEscaped)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.Collections.Concurrent.Count<Int32>

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

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

| 49.39 ns | 45.51 ns | 0.92 | 0.05 | 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.Concurrent.Count*'
```

### System.Collections.Concurrent.Count<Int32>.Dictionary(Size: 512)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

---

### Run Information

### Improvements in System.Tests.Perf_Enum

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

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

| 77.71 ns | 64.69 ns | 0.83 | 0.13 | 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.Tests.Perf_Enum*'
```

### System.Tests.Perf_Enum.ToString_Format_Flags_Large(value: All, format: "d")

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

Contributor guide

No contributing guide indexed for this repository

Research direction

Start with the benchmark sources named in src/benchmarks/micro/libraries/System.Collections/Create/CtorFromCollection.cs, Iterate/IterateForEach.cs, and System.Text.Json/Utf8JsonWriter/Perf.Strings.cs. Run the listed benchmarks with benchmarks_ci.py and compare the reported results with the linked baseline and test reports. The issue does not define a code change or acceptance criteria, so completion would require triage to identify an actionable performance change.

Written by the indexing model from the issue text.

Assessment

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

[Perf] Linux/x64: 5 Improvements on 8/4/2026 8:53:30 PM +00:00

Description

Contributor guide

Research direction

Assessment

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