New Index on table cause table to be locked really often

Here are my tables :

CREATE TABLE [dbo].[Trackers] (
    [IdTracker]             INT           IDENTITY (1, 1) NOT NULL,
    [IMEI]                  NVARCHAR (16) NULL,
    [CreationDate]          DATETIME      NULL,
    [SuppressionDate]       DATETIME      NULL,
    [LastUpdateDate]        DATETIME      NULL,
    [BuyDate]               DATETIME      NOT NULL,
    [Status]                INT           NOT NULL,
    [LastTrackerUpdateDate] DATETIME      NULL,
    [IdLastTrackerPosition] INT           NULL,
    PRIMARY KEY CLUSTERED ([IdTracker] ASC)
);

CREATE TABLE [dbo].[TrackerPositions] (
    [IdTrackerPosition] INT               IDENTITY (1, 1) NOT NULL,
    [TrackerId]         INT               NOT NULL,
    [Position]          [sys].[geography] NULL,
    [Date]              DATETIME          NOT NULL,
    [Speed]             REAL              NULL,
    [NbSatellites]      TINYINT           NULL,
    [Direction]         REAL              NULL,
    [HDOP]              REAL              NULL,
    PRIMARY KEY CLUSTERED ([IdTrackerPosition] ASC),
    CONSTRAINT [TrackerTrackerPosition] FOREIGN KEY ([TrackerId]) REFERENCES [dbo].     [Trackers] ([IdTracker])
 );

Tracker position is used to store positions send by car trackers. So I have a lot of insert going on.
And I often need to get the last position known for a tracker.

So here is a query generated by Entity Framework :

```
SELECT
[Limit1].[IdTrackerPosition] AS [IdTrackerPosition],
[Limit1].[TrackerId] AS [TrackerId],
[Limit1].[Position] AS [Position],
[Limit1].[Date] AS [Date],
[Limit1].[Speed] AS [Speed],
[Limit1].[NbSatellites] AS [NbSatellites],
[Limit1].[Direction] AS [Direction],
[Limit1].[HDOP] AS [HDOP]
FROM (SELECT DISTINCT
[Extent1].[TrackerId] AS [TrackerId]
FROM [dbo].[TrackerPositions] AS [Extent1]
WHERE ([Extent1].[Position] IS NOT NULL) AND ([Extent1].[TrackerId] IN (1, 48)) ) AS [Distinct1]
OUTER APPLY (SE

Your index should be on (TrackerId ASC, [Date] DESC) INCLUDE (Position) so that it can easily locate the most recent one for each Tracker.

But I really don't like the query from EF.

Edit:
...because "most recent" should mean "latest datetime", not "latest identity value"

StackExchange Database Administrators Q#86681, answer score: 4