dotnet / dotnet/perf-autofiling-issues

[Perf] Linux/x64: 52 Improvements on 7/14/2026 4:54:43 PM +00:00

Open
#76,368 2 comments 0 reactions 0 assignees View on GitHub
aot-true arch-wasm arch-x64 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 metrics pending

Description

### Run Information

Name | Value
-- | --
Architecture | x64
OS | ubuntu 22.04
Queue | ViperUbuntu
Baseline | [1baa904ac12c971494469fc724fb3b9f7126716d](https://github.com/dotnet/runtime/commit/1baa904ac12c971494469fc724fb3b9f7126716d)
Compare | [646ab80e65fcf3cb9f068157f644ead63761ee7c](https://github.com/dotnet/runtime/commit/646ab80e65fcf3cb9f068157f644ead63761ee7c)
Diff | [Diff](https://github.com/dotnet/runtime/compare/1baa904ac12c971494469fc724fb3b9f7126716d...646ab80e65fcf3cb9f068157f644ead63761ee7c)
Configs | AOT:true, CompilationMode:wasm, RunKind:micro

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

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

  • [ReadSingleSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 14.64 μs | 7.27 μs | 0.50 | 0.07 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 21.22 μs | 11.46 μs | 0.54 | 0.07 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 13.25 μs | 7.32 μs | 0.55 | 0.11 | False | | |
|
  • [ReadSingleSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 3.46 μs | 1.92 μs | 0.56 | 0.09 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 22.87 μs | 12.74 μs | 0.56 | 0.08 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 131.49 μs | 73.41 μs | 0.56 | 0.11 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 3.37 μs | 1.91 μs | 0.57 | 0.11 | False | | |
|
  • [ReadSingleSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 20.70 μs | 11.81 μs | 0.57 | 0.06 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 146.70 μs | 84.64 μs | 0.58 | 0.08 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 14.45 μs | 8.38 μs | 0.58 | 0.11 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 1614.91 ns | 939.44 ns | 0.58 | 0.09 | False | | |
|
  • [ReadSingleSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 1636.79 ns | 955.43 ns | 0.58 | 0.07 | False | | |
|
  • [ReadSingleSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 129.53 μs | 76.26 μs | 0.59 | 0.09 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 3.83 μs | 2.26 μs | 0.59 | 0.08 | False | | |
|
  • [ReadSingleSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 5.09 μs | 3.01 μs | 0.59 | 0.05 | False | | |
|
  • [ReadMultiSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 143.83 μs | 85.09 μs | 0.59 | 0.13 | False | | |
|
  • [ReadMultiSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 23.10 μs | 13.80 μs | 0.60 | 0.07 | False | | |
|
  • [ReadMultiSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 14.44 μs | 8.69 μs | 0.60 | 0.06 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 5.62 μs | 3.40 μs | 0.60 | 0.11 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 1.74 μs | 1.07 μs | 0.61 | 0.11 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 242.26 ns | 149.54 ns | 0.62 | 0.17 | False | | |
|
  • [ReadMultiSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 6.30 μs | 3.98 μs | 0.63 | 0.14 | False | | |
|
  • [ReadMultiSpanSequenceEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 2.02 μs | 1.30 μs | 0.64 | 0.08 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 10.43 μs | 6.75 μs | 0.65 | 0.06 | False | | |
|
  • [ReadSpanEmptyLoop - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 201.57 ns | 130.76 ns | 0.65 | 0.16 | False | | |
|
  • [ReadReturnBytes - Duration of single invocation]()
  • 📝 - [Benchmark Source]()
  • [ADX - Test Multi Config Graph]()
| 11.01 μs | 7.52 μs | 0.68 | 0.09 | False | | |

![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![graph]()
![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.Text.Json.Tests.Perf_Reader*'
```

### System.Text.Json.Tests.Perf_Reader.ReadSingleSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: Json4KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: BroadTree)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: Json4KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSingleSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: LotsOfStrings)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: BroadTree)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: Json40KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: LotsOfStrings)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSingleSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: BroadTree)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: Json40KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: Json4KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: Json400B)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSingleSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: Json400B)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSingleSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: Json40KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: LotsOfStrings)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSingleSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: LotsOfNumbers)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadMultiSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: Json40KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadMultiSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: BroadTree)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadMultiSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: Json4KB)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: LotsOfNumbers)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: Json400B)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: HelloWorld)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadMultiSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: LotsOfNumbers)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadMultiSpanSequenceEmptyLoop(IsDataCompact: False, TestCase: Json400B)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: DeepTree)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadSpanEmptyLoop(IsDataCompact: False, TestCase: HelloWorld)

#### ETL Files

#### Histogram

#### JIT Disasms

### System.Text.Json.Tests.Perf_Reader.ReadReturnBytes(IsDataCompact: False, TestCase: DeepTree)

#### 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)

Contributor guide

No contributing guide indexed for this repository

Research direction

Start with the referenced benchmark source at src/benchmarks/micro/libraries/System.Text.Json/Utf8JsonReader/Perf.Reader.cs, especially the ReadSpanEmptyLoop, ReadSingleSpanSequenceEmptyLoop, and ReadReturnBytes ranges. Review the reported baseline and comparison results to determine whether any change is actually required; the issue does not define an implementation target or completion criteria.

Written by the indexing model from the issue text.

Assessment

Tech stack
csharp, linux, ubuntu, wasm
Domain
performance, testing-qa
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
20/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.