Performance and Benchmarks

[jaredcnance]

• profile the examples apps to determine hot paths
• setup a benchmarkdotnet project
• write benchmarks for known hot paths
• optimize based on benchmarks

Known Issues:

• improper use of List / IEnumerable:
  • allocating a new list just to forEach it:

    • JsonApiDotNetCore/src/JsonApiDotNetCore/Services/QueryParser.cs

      Line 140 in 0664c3d

      value.Split(',').ToList().ForEach(p =>

• using string literals instead of const:

  • JsonApiDotNetCore/src/JsonApiDotNetCore/Services/QueryParser.cs

    Line 104 in 0664c3d

    var operation = value.Split(':');

  • JsonApiDotNetCore/src/JsonApiDotNetCore/Services/QueryParser.cs

    Line 114 in 0664c3d

    value = string.Join(":", operation.Skip(1));

  • JsonApiDotNetCore/src/JsonApiDotNetCore/Formatters/JsonApiOutputFormatter.cs

    Line 17 in 0664c3d

    return string.IsNullOrEmpty(contentTypeString) || contentTypeString == "application/vnd.api+json";

• Can we improve performance by providing generic overloads with constraints over type checking:
  • instead of:
    

    JsonApiDotNetCore/src/JsonApiDotNetCore/Models/Identifiable.cs

    Lines 26 to 30 in 0664c3d

    	if(type == typeof(Guid))
    	{
    	var guid = Guid.Parse(stringValue);
    	return guid == Guid.Empty ? string.Empty : stringValue;
    	}

  • can we do something like:

public class Identifiable<T> : IIdentifiable<T> where T : Guid {
  // ...
}

• Use BaseController instead of Controller
• Use .AsNoTracking() on read-only queries
• Use .Attach(/*..*/) instead of first calling GetAsync(/*..*/) in PATCH requests
  

  JsonApiDotNetCore/src/JsonApiDotNetCore/Data/DefaultEntityRepository.cs

  Lines 120 to 133 in ef147e4

  	public virtual async Task<TEntity> UpdateAsync(TId id, TEntity entity)
  	{
  	var oldEntity = await GetAsync(id);
  	if (oldEntity == null)
  	return null;
  	foreach (var attr in _jsonApiContext.AttributesToUpdate)
  	attr.Key.SetValue(oldEntity, attr.Value);
  	foreach (var relationship in _jsonApiContext.RelationshipsToUpdate)
  	relationship.Key.SetValue(oldEntity, relationship.Value);
  	await _context.SaveChangesAsync();