[mono][Perf] AOT-llvm BigInteger.Substract regression on 5/31/2024 7:00:20 PM

performanceautofiler[bot] commented 3 months ago

Run Information

Name	Value
Architecture	x64
OS	ubuntu 22.04
Queue	TigerUbuntu
Baseline	9fca0c3dbd3874ed0245b1bdb10547d0ba769d66
Compare	d8c59a418e0857d2bdf71eea064cd6e55a093092
Diff	Diff
Configs	CompilationMode:tiered, LLVM:true, MonoAOT:true, MonoInterpreter:false, RunKind:micro_mono

Regressions in System.Numerics.Tests.Perf_BigInteger

Benchmark	Baseline	Test	Test/Base	Test Quality	Edge Detector	Baseline IR	Compare IR	IR Ratio
[Subtract - Duration of single invocation](<https://pvscmdupload.z22.web.core.windows.net/reports/allTestHistory/refs/heads/main_x64_ubuntu 22.04_LLVM=true_MonoAOT=true_MonoInterpreter=false_RunKind=micro_mono/System.Numerics.Tests.Perf_BigInteger.Subtract(arguments%3a%201024%2c1024%20bits).html>) 📝 - Benchmark Source ADX - Test Multi Config Graph	106.53 ns	118.82 ns	1.12	0.02	False

graph Test Report

Repro

General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

Repro Steps

#### Prerequisites (Files either built locally (with build.(sh/cmd) or downloaded from payload above (if same system setup) (in this order)) - Libraries build extracted to `runtime/artifacts` or build instructions: [Libraries README](https://github.com/dotnet/runtime/blob/main/docs/workflow/building/libraries/README.md) args: `-subset libs+libs.tests -rc release -configuration Release -arch $RunArch -framework net8.0` - CoreCLR product build extracted to `runtime/artifacts/bin/coreclr/$RunOS.$RunArch.Release`, build instructions: [CoreCLR README](https://github.com/dotnet/runtime/blob/main/docs/workflow/building/coreclr/README.md) args: `-subset clr+libs -rc release -configuration Release -arch $RunArch -framework net8.0` - AOT MONO build extracted to `runtime/artifacts/bin/mono/$RunOS.$RunArch.Release`, build instructions: [MONO README](https://github.com/dotnet/runtime/blob/main/docs/workflow/building/mono/README.md) args: `-arch $RunArch -os $RunOS -s mono+libs+host+packs -c Release /p:CrossBuild=false /p:MonoLLVMUseCxx11Abi=false` - Dotnet SDK installed for dotnet commands - Running commands from the runtime folder Linux ```cmd # Set $RunDir to the runtime directory RunDir=`pwd` # Set the OS, arch, and OSId RunOS='linux' RunOSId='linux' RunArch='x64' # Create aot directory mkdir -p $RunDir/artifacts/bin/aot/sgen mkdir -p $RunDir/artifacts/bin/aot/pack cp -r $RunDir/artifacts/obj/mono/$RunOS.$RunArch.Release/mono/* $RunDir/artifacts/bin/aot/sgen cp -r $RunDir/artifacts/bin/microsoft.netcore.app.runtime.$RunOS-$RunArch/Release/* $RunDir/artifacts/bin/aot/pack # Create Core Root $RunDir/src/tests/build.sh release $RunArch generatelayoutonly /p:LibrariesConfiguration=Release # Clone performance git clone --branch main --depth 1 --quiet https://github.com/dotnet/performance.git $RunDir/performance # One line run: python3 $RunDir/performance/scripts/benchmarks_ci.py --csproj $RunDir/performance/src/benchmarks/micro/MicroBenchmarks.csproj --incremental no --architecture $RunArch -f net8.0 --filter 'System.Numerics.Tests.Perf_BigInteger*' --bdn-artifacts $RunDir/artifacts/BenchmarkDotNet.Artifacts --bdn-arguments="--anyCategories Libraries Runtime --category-exclusion-filter NoAOT NoWASM --runtimes monoaotllvm --aotcompilerpath $RunDir/artifacts/bin/aot/sgen/mini/mono-sgen --customruntimepack $RunDir/artifacts/bin/aot/pack --aotcompilermode llvm --logBuildOutput --generateBinLog" # Individual Commands: # Restore dotnet restore $RunDir/performance/src/benchmarks/micro/MicroBenchmarks.csproj --packages $RunDir/performance/artifacts/packages /p:UseSharedCompilation=false /p:BuildInParallel=false /m:1 # Build dotnet build $RunDir/performance/src/benchmarks/micro/MicroBenchmarks.csproj --configuration Release --framework net8.0 --no-restore /p:NuGetPackageRoot=$RunDir/performance/artifacts/packages /p:UseSharedCompilation=false /p:BuildInParallel=false /m:1 # Run dotnet run --project $RunDir/performance/src/benchmarks/micro/MicroBenchmarks.csproj --configuration Release --framework net8.0 --no-restore --no-build -- --filter System.Numerics.Tests.Perf_BigInteger* --anyCategories Libraries Runtime " --category-exclusion-filter NoAOT NoWASM --runtimes monoaotllvm --aotcompilerpath $RunDir/artifacts/bin/aot/sgen/mini/mono-sgen --customruntimepack $RunDir/artifacts/bin/aot/pack --aotcompilermode llvm --logBuildOutput --generateBinLog " --artifacts $RunDir/artifacts/BenchmarkDotNet.Artifacts --packages $RunDir/performance/artifacts/packages --buildTimeout 1200 ``` Windows ```cmd # Set $RunDir to the runtime directory $RunDir="FullPathHere" # Set the OS, arch, and OSId RunOS='windows' RunOSId='win' RunArch='x64' # Create aot directory mkdir $RunDir\artifacts\bin\aot\sgen mkdir $RunDir\artifacts\bin\aot\pack xcopy $RunDir\artifacts\obj\mono\$RunOS.$RunArch.Release\mono $RunDir\artifacts\bin\aot\sgen\ /e /y xcopy $RunDir\artifacts\bin\microsoft.netcore.app.runtime.$RunOSId-$RunArch\Release $RunDir\artifacts\bin\aot\pack\ /e /y # Create Core Root $RunDir\src\tests\build.cmd release $RunArch generatelayoutonly /p:LibrariesConfiguration=Release # Clone performance git clone --branch main --depth 1 --quiet https://github.com/dotnet/performance.git $RunDir\performance # One line run: python3 $RunDir\performance\scripts\benchmarks_ci.py --csproj $RunDir\performance\src\benchmarks\micro\MicroBenchmarks.csproj --incremental no --architecture $RunArch -f net8.0 --filter 'System.Numerics.Tests.Perf_BigInteger*' --bdn-artifacts $RunDir\artifacts\BenchmarkDotNet.Artifacts --bdn-arguments="--anyCategories Libraries Runtime --category-exclusion-filter NoAOT NoWASM --runtimes monoaotllvm --aotcompilerpath $RunDir\artifacts\bin\aot\sgen\mini\mono-sgen.exe --customruntimepack $RunDir\artifacts\bin\aot\pack --aotcompilermode llvm --logBuildOutput --generateBinLog" # Individual Commands: # Restore dotnet restore $RunDir\performance\src\benchmarks\micro\MicroBenchmarks.csproj --packages $RunDir\performance\artifacts\packages /p:UseSharedCompilation=false /p:BuildInParallel=false /m:1 # Build dotnet build $RunDir\performance\src\benchmarks\micro\MicroBenchmarks.csproj --configuration Release --framework net8.0 --no-restore /p:NuGetPackageRoot=$RunDir\performance\artifacts\packages /p:UseSharedCompilation=false /p:BuildInParallel=false /m:1 # Run dotnet run --project $RunDir\performance\src\benchmarks\micro\MicroBenchmarks.csproj --configuration Release --framework net8.0 --no-restore --no-build -- --filter System.Numerics.Tests.Perf_BigInteger* --anyCategories Libraries Runtime " --category-exclusion-filter NoAOT NoWASM --runtimes monoaotllvm --aotcompilerpath $RunDir\artifacts\bin\aot\sgen\mini\mono-sgen.exe --customruntimepack $RunDir\artifacts\bin\aot\pack -aotcompilermode llvm --logBuildOutput --generateBinLog " --artifacts $RunDir\artifacts\BenchmarkDotNet.Artifacts --packages $RunDir\performance\artifacts\packages --buildTimeout 1200 ```

### System.Numerics.Tests.Perf_BigInteger.Subtract(arguments: 1024,1024 bits) #### 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)

matouskozak commented 2 months ago

Could it be related to https://github.com/dotnet/runtime/pull/102874 and is the regression expected @tannergooding ?

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tannergooding commented 2 months ago

It's possible. The change included some cleanup to use span.LastIndexOf instead of a hand rolled loop and it's possible that regressed perf if the handling isn't as good on Mono.

I believe Mono is accelerated in this case, so it could be caused by something not getting inlined or tracked instead. Is there an easy way to see the disasm diff for Mono here? It should come down to the codegen for private BigInteger(ReadOnlySpan<uint> value, bool negative), potentially public static unsafe int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value) where T : IEquatable<T>?

matouskozak commented 2 months ago

It's possible. The change included some cleanup to use span.LastIndexOf instead of a hand rolled loop and it's possible that regressed perf if the handling isn't as good on Mono.

I believe Mono is accelerated in this case, so it could be caused by something not getting inlined or tracked instead. Is there an easy way to see the disasm diff for Mono here? It should come down to the codegen for private BigInteger(ReadOnlySpan<uint> value, bool negative), potentially public static unsafe int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value) where T : IEquatable<T>?

Thank you for the insight. I think that running Mono with MONO_VERBOSE_METHOD=<method_name> will dump the generated assembly into terminal.

matouskozak commented 2 months ago

Mono arm64 AOT-llvm regression: https://github.com/dotnet/perf-autofiling-issues/issues/35612

dotnet / runtime