Question

我正在研究应用程序的缓慢性能（页面在Azure上加载8秒以上），并发现有趣的事情。

以下代码执行时间约为0.318秒

        var reservations = db.Reservations.Include(r => r.PickUpLocation);
        var reservationsList = reservations.ToList();

但是如果我手动加载导航属性，它将完成2.5倍（0.128秒）。

        var reservations = db.Reservations.ToList();
        var locations = db.Locations.ToList();

        foreach (var r in reservations)
        {
            r.PickUpLocation = locations.FirstOrDefault(l => l.ID == r.PickUpLocationID);
        }

对于更复杂的查询，差异甚至更高 - 最多20次（例如8秒与0.8秒）。

我尝试了QueryTrackingBehavior.NoTracking和QueryTrackingBehavior.TrackAll，对性能没有显着影响。

此外，我注意到实时Azure比本地计算机慢10倍，并且在EF /手动方法之间显示出更高的性能差异。

有没有办法让EF工作更快？

更新位置表有121行（6个字符串列，1个布尔值和2个int）预订表有1268行

预订模型类的重要部分：

public class Reservation
{
    public int ID { get; set; }

    ...

    [ForeignKey("PickUpLocation")]
    public int PickUpLocationID { get; set; }
    public Location PickUpLocation { get; set; }

    ...
}

位置模型类：

public class Location
{
    public int ID { get; set; }

    [StringLength(100)]
    public string Name { get; set; }

    [StringLength(255)]
    public string Address { get; set; }

    [StringLength(25)]
    public string Barangay { get; set; }

    [StringLength(25)]
    public string City { get; set; }

    [StringLength(25)]
    public string Province { get; set; }

    [StringLength(20)]
    public string Country { get; set; }

    [Display(Name = "Service Type")]
    public LocationServiceType? ServiceType { get; set; }

    [Display(Name = "Location Type")]
    [Required]
    public LocationType? LocationType { get; set; }

    public bool IsDeleted { get; set; }
}

在执行详细登录的应用程序时，我可以看到实际执行的SQL查询。 EF7只做一个查询：

  Executed DbCommand (5ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
  SELECT [r].[ID], [r].[AssignedUnitID], [r].[AssignedUnitThirdParty], [r].[BookingCode], [r].[Comments], [r].[DailyPriceID], [r].[DamageDescription], [r].[DocumentCountry], [r].[DocumentNumber], [r].[DocumentOwnerName], [r].[DocumentType], [r].[Email], [r].[FirstName], [r].[FlightArrival], [r].[FlightNumber], [r].[HomeAddress], [r].[LastName], [r].[Phone], [r].[PickUpDateTime], [r].[PickUpLocationID], [r].[RequestedVehicleModelID], [r].[RequestedVehicleTypeID], [r].[ReturnDateTime], [r].[ReturnLocationID], [r].[State], [r].[StayingAddress], [r].[ThirdPartyName], [r].[Type], [r].[UserId], [r].[VersionDate], [l].[ID], [l].[Address], [l].[Barangay], [l].[City], [l].[Country], [l].[IsDeleted], [l].[LocationType], [l].[Name], [l].[Province], [l].[ServiceType]
  FROM [Reservation] AS [r]
  INNER JOIN [Location] AS [l] ON [r].[PickUpLocationID] = [l].[ID]

所以问题必须在于它如何解析结果。

EF7包含的慢表现（）

0 个答案: