MongoClient的生命周期应该如何工作？

Question

我有一个使用MongoDB作为数据库的ASP.Net MVC应用程序.网站和数据库位于不同的服务器上.

目前,我有一个看起来像这样的课程:

public class Mongo
{
    private IMongoDatabase database;

    public Mongo()
    {
        var client = new MongoClient("mongodb://username:password@ipaddress:port");
        database = client.GetDatabase("MyDatabase");
    }

    public IMongoCollection<ApplicationUser> Users() { return database.GetCollection<ApplicationUser>("Users"); }
}

所以要使用它...(基本上在每个请求中)

Mongo mon = new Mongo();
mon.Users.Find(........); // etc.

这项工作正常 - 大部分时间都是如此.在奇怪的情况下,事情似乎锁定,数据库只是超时,直到我重新启动网站.我在尝试连接数据库服务器时遇到超时错误.

在这种情况下,数据库服务器已经确认,我可以从另一个mongo客户端连接到MongoDB而不会出现问题.

我意识到这里没有"紧密联系"的事情 - 但似乎没有一个人甚至打电话.所以我想知道是否有太多的连接被打开而没有正确清理.

我使用MongoClient不正确吗？有什么明显的东西我应该做些什么来阻止这些超时？

这是我得到的错误的痕迹:

   [SocketException (0x274c): A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond ipaddress:port]
       System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult) +6768957
       System.Threading.Tasks.TaskFactory`1.FromAsyncCoreLogic(IAsyncResult iar, Func`2 endFunction, Action`1 endAction, Task`1 promise, Boolean requiresSynchronization) +57
       System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
       System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
       System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task) +25
       MongoDB.Driver.Core.Connections.<ConnectAsync>d__7.MoveNext() +1542
       System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
       System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
       MongoDB.Driver.Core.Connections.<CreateStreamAsync>d__0.MoveNext() +345
       System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
       System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
       MongoDB.Driver.Core.Connections.<OpenAsyncHelper>d__1.MoveNext() +553

[MongoConnectionException: An exception occurred while opening a connection to the server.]
   MongoDB.Driver.Core.Connections.<OpenAsyncHelper>d__1.MoveNext() +1372
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
   MongoDB.Driver.Core.Servers.<GetChannelAsync>d__0.MoveNext() +548
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
   System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task) +25
   MongoDB.Driver.Core.Operations.<ExecuteAsync>d__2.MoveNext() +639
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
   MongoDB.Driver.<ExecuteReadOperationAsync>d__0`1.MoveNext() +272
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
   MongoDB.Driver.<ExecuteReadOperation>d__35`1.MoveNext() +396
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +99
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +58
   MongoDB.Driver.<ToListAsync>d__14`1.MoveNext() +294

Answer 1

您使用MongoClient不当.如文档中所示

建议将MongoClient实例存储在全局位置,可以是静态变量,也可以是具有单例生存期的IoC容器.

因此,您应该重新编写代码以创建单例MongoClient实例,然后在整个程序中使用它.

原因是MongoClient维护一个可以共享和重用的开放连接池以获得最佳性能.