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NET 8.0 Preview 7 Performance Regression: ActivatorUtilities.CreateInstance #91186
Description
Description
I was checking new behavior for "ActivatorUtilities.CreateInstance" in NET 8.0 and noticed some perfomance regression when invoked for class with not empty construcor, as i can see something changed between "Preview 6" and "Preview 7", it's slighly better in last daily build "rc.2.23426.4" but still much worse than NET7.0 .
public class Tester
{
private static IServiceProvider _spProvider;
public Tester()
{
var sc = new ServiceCollection();
sc.AddScoped<A>();
sc.AddScoped<B>();
sc.AddScoped<C>();
_spProvider = sc.BuildServiceProvider();
}
public A? CreateA()
{
var scope = _spProvider.CreateScope();
return ActivatorUtilities.CreateInstance<A>(scope.ServiceProvider);
}
public B? CreateB()
{
var scope = _spProvider.CreateScope();
return ActivatorUtilities.CreateInstance<B>(scope.ServiceProvider);
}
public C? CreateC()
{
var scope = _spProvider.CreateScope();
return ActivatorUtilities.CreateInstance<C>(scope.ServiceProvider);
}
}
public class A
{ }
public class B
{
private readonly A _a;
public B(A a)
{
_a = a;
}
}
public class C
{
private readonly B _b;
private readonly B _b1;
private readonly B _b2;
private readonly B _b3;
private readonly B _b4;
private readonly B _b5;
public C(B b, B b1, B b2, B b3, B b4, B b5)
{
_b = b;
_b1 = b1;
_b2 = b2;
_b3 = b3;
_b4 = b4;
_b5 = b5;
}
}
Configuration
BenchmarkDotNet v0.13.7, Windows 10 (10.0.19044.3086/21H2/November2021Update)
11th Gen Intel Core i5-11600K 3.90GHz, 1 CPU, 12 logical and 6 physical cores
.NET SDK 8.0.100-rc.2.23425.18
[Host] : .NET 7.0.1 (7.0.122.56804), X64 RyuJIT AVX2
7.0.0 : .NET 7.0.1 (7.0.122.56804), X64 RyuJIT AVX2
8.0.0-preview.6.23329.7 : .NET 8.0.0 (8.0.23.42311), X64 RyuJIT AVX2
8.0.0-preview.7.23375.6 : .NET 8.0.0 (8.0.23.42311), X64 RyuJIT AVX2
8.0.0-rc.2.23426.4 : .NET 8.0.0 (8.0.23.42311), X64 RyuJIT AVX2
Regression?
Data
| Method | Runtime | NuGetReferences | Mean | Error | StdDev | Ratio |
|---|---|---|---|---|---|---|
| CreateA | .NET 7.0 | Microsoft.Extensions.DependencyInjection 7.0.0 | 122.1 ns | 2.05 ns | 1.92 ns | baseline |
| CreateA | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-preview.6.23329.7 | 116.8 ns | 2.33 ns | 2.50 ns | -4% |
| CreateA | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-preview.7.23375.6 | 113.6 ns | 1.54 ns | 1.44 ns | -7% |
| CreateA | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-rc.2.23426.4 | 119.0 ns | 2.42 ns | 2.69 ns | -3% |
| CreateB | .NET 7.0 | Microsoft.Extensions.DependencyInjection 7.0.0 | 220.3 ns | 3.31 ns | 3.10 ns | baseline |
| CreateB | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-preview.6.23329.7 | 218.9 ns | 3.83 ns | 3.39 ns | -1% |
| CreateB | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-preview.7.23375.6 | 480.0 ns | 3.31 ns | 2.76 ns | +118% |
| CreateB | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-rc.2.23426.4 | 402.6 ns | 4.53 ns | 4.24 ns | +83% |
| CreateC | .NET 7.0 | Microsoft.Extensions.DependencyInjection 7.0.0 | 522.9 ns | 4.21 ns | 3.73 ns | baseline |
| CreateC | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-preview.6.23329.7 | 494.1 ns | 3.49 ns | 2.91 ns | -5% |
| CreateC | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-preview.7.23375.6 | 2,489.0 ns | 26.57 ns | 24.85 ns | +376% |
| CreateC | .NET 8.0 | Microsoft.Extensions.DependencyInjection 8.0.0-rc.2.23426.4 | 1,604.6 ns | 26.34 ns | 23.35 ns | +207% |
Activity
stephentoub commentedon Aug 28, 2023
cc: @steveharter
steveharter commentedon Aug 28, 2023
Currently verifying this issue to see if same as reported in #89104
steveharter commentedon Aug 28, 2023
This is a regression from the "keyed services" feature due to reading custom attributes. In this case, it is the
FromKeyedServicesAttributeperParameterInfowhich in a quick prototype showed that caching this in a dictionary will get very close to 7.0 perf. Working on this now.steveharter commentedon Aug 29, 2023
Using a dictionary to hold the
ParameterInfoper above does get us back to almost 7.0, but doing a full cache on all of the ConstructorInfo state yields a much better result:7.0:
8.0:
After:
steveharter commentedon Aug 29, 2023
Setting to v9; will get feedback on whether to port to v8.
[-]NET 8.0 Preview 7 Perfomance Regression: ActivatorUtilities.CreateInstance[/-][+]NET 8.0 Preview 7 Performance Regression: ActivatorUtilities.CreateInstance[/+]stephentoub commentedon Aug 30, 2023
I think it'd be good to fix this for 8.
stephentoub commentedon Sep 11, 2023
Reopening to track backport.
steveharter commentedon Sep 12, 2023
Closing; fixed in backport