用 Dapper 持续查询，发现耗时越来越长，代码如下：

var page = 0;
var pageSize = 10;
var count = pageSize;
var sw = new Stopwatch();

while (count >= pageSize)
{
    sw.Restart();
    count = await Query(page, pageSize, startId, maxId);
    sw.Stop();
    _logger.LogInformation($"Query {count} items with {sw.ElapsedMilliseconds}ms");
    page++;
}

private async Task<int> Query(int page, int pageSize, int startId, int maxId)
{
var sql = @"SELECT [t].[Id], 
                   [t].[Title],
                   [t].[Content], 
            FROM (
                    SELECT [x].[Id], 
                           [x].[Title], 
                           [x].[Content], 
                           ROW_NUMBER() OVER(ORDER BY [x].[Id]) AS [__RowNumber__]
                    FROM [Items] AS [x]
                    WHERE ([x].[Id] > @startId) AND ([x].[Id] <= @maxId)
                ) AS [t]
            WHERE ([t].[__RowNumber__] > @p1) AND ([t].[__RowNumber__] <= (@p1 + @p2))";

var items = _connection.Query<Item>(sql, new { startId = startId, maxId = maxId, p1 = page * pageSize, p2 = pageSize });
retrun items.Count();
}

打印出来的时间从一开始 10 ms，在8个小时内慢慢的增加到 5000 ms，请问这是什么原因呢？