roji
commented
3 years ago There are GC everywhere but what is getting garbage collected? At least for tracking kind of scenario, we are not getting any reference out of scope.
I'd (first) concentrate on the "Allocated" column, which really accurately tells us how much is allocated during the method invocation.
Re [IterationSetup], I understand that you want to separate out context creation and disposal, but note that its use is discouraged for benchmarks of less than 100ms. Of course, creating and disposing in the benchmark method also skews results - I don't know enough to know what's more accurate.
In any case, what's particularly important here is the relative values across tracking behaviors, so this doesn't seem that relevant.
smitpatel
public class Program { public static void Main(string[] args) { BenchmarkRunner.Run();
}
}
[MemoryDiagnoser]
public class QueryTrackingBehavior
{
private BloggingContext _context;
[Params(1000)]
public int NumBlogs { get; set; }
[Params(100)]
public int NumPostsPerBlog { get; set; }
[GlobalSetup]
public void Setup()
{
Console.WriteLine("Setting up database...");
using var context = new BloggingContext();
context.Database.EnsureDeleted();
context.Database.EnsureCreated();
context.SeedData(NumBlogs, NumPostsPerBlog);
Console.WriteLine("Setup complete.");
}
[IterationSetup]
public void CreateContext()
{
_context = new BloggingContext();
_context.ChangeTracker.QueryTrackingBehavior = Microsoft.EntityFrameworkCore.QueryTrackingBehavior.NoTrackingWithIdentityResolution;
}
[IterationCleanup]
public void DisposeContext()
{
_context.Dispose();
}
[Benchmark]
public void Tracking()
{
foreach (var item in _context.Posts.AsTracking()/*.Include(p => p.Blog)*/)
{
}
}
[Benchmark]
public void NoTracking()
{
foreach (var item in _context.Posts.AsNoTracking()/*.Include(p => p.Blog)*/)
{
}
}
[Benchmark]
public void NoTrackingWithIdentityResolution()
{
foreach (var item in _context.Posts/*.Include(p => p.Blog)*/)
{
}
}
public class BloggingContext : DbContext
{
public DbSet Blogs { get; set; }
public DbSet Posts { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
optionsBuilder.UseSqlServer(
@"Server=SLDW;Database=test;Trusted_Connection=True;;Connect Timeout=60;ConnectRetryCount=0");
// @"Server=(localdb)\mssqllocaldb;Database=Blogging;Integrated Security=True");
}
public void SeedData(int numBlogs, int numPostsPerBlog)
{
using var context = new BloggingContext();
context.AddRange(
Enumerable.Range(0, numBlogs).Select(_ => new Blog
{
Posts = Enumerable.Range(0, numPostsPerBlog).Select(_ => new Post()).ToList()
}));
context.SaveChanges();
}
}
public class Blog
{
public int BlogId { get; set; }
public string Url { get; set; }
public int Rating { get; set; }
public List Posts { get; set; }
}
public class Post
{
public int PostId { get; set; }
public string Title { get; set; }
public string Content { get; set; }
public int BlogId { get; set; }
public Blog Blog { get; set; }
}
}
The AsTracking operator has no effect in the result how it is configured.
Few ideas
Improvements for NoTrackingWithIdentityResolution
Came out discussion with @roji