集群一致哈希池为相同映射生成新路由 [英] clustered consistent hash pool producing new routee for same mapping

问题描述

我有一个包含2个命令行项目的解决方案，它们创建了一个带有种子和客户端进程的akka​​.net集群.种子启动集群，然后实例化一个consistent-hash-cluster-router，该路由器对实现我的接口"IHasRouting"的任何消息执行哈希映射.因此，任何(来自种子或客户端的)IHasRouting消息都应以该消息的散列在路由上的种子处结束.

I have a solution with 2 command line projects that creates an akka.net cluster with a seed and client process. The seed starts the cluster and then instantiates a consistent-hash-cluster-router that performs hash mapping on any message that implements my interface "IHasRouting". So any IHasRouting message (from the seed or client) should end up at seed on a routee for the hash of that message.

项目正常启动，并且群集形成没有错误.种子和客户端都实例化路由器.来自种子和客户端的所有消息都具有相同的"VolumeId"，因此它们应在种子处使用相同的路由. 来自客户端节点的BUT消息会在种子处为这些消息产生新的路由！

The projects start fine and the cluster forms without error. Both seed and client instantiate a router. All messages from the seed and client have the same "VolumeId" so they should go to the same route at the seed. BUT Messages from the client node result in a new routee for those messages at the seed!

我对一致性哈希路由器的理解是:

My understanding of a consistent-hash-cluster-router is that:

• 包含IActorRef的IActorRef应该在该节点上的参与者要向路由器发送消息的每个节点上退出.
• 路由器的权限在每个节点上应该相同，并且参与者名称相同.
• 所有发送到路由器的消息都应实现IConsistentHash或路由器实例应具有"WithHashMapping()"
• 所有具有相同哈希值的邮件将仅到达一个路由，并且始终是相同的路由
• 一个路由可能会使用多个哈希值

我相信我了解一致的哈希群集路由器应该如何工作，并且许多DEV似乎正确使用了路由器类型，因此我的实现一定是错误的...请帮助！如果有帮助，我可以提供完整的解决方案.

I believe I understand how a consistent-hash-cluster-router should behave and plenty of the DEVs would appear to be using the router type correctly so my implementation must be wrong... Please help! I can provide the full solution if that helps.

创建路由器的代码:

system.ActorOf(
   new ClusterRouterPool(
       local: new ConsistentHashingPool(nrOfInstances: 1)
          .WithHashMapping(m => (m as IHasRouting)?.Company?.VolumeId ?? throw new Exception("no routing!")),
                settings: new ClusterRouterPoolSettings(
                    100,
                    100,
                    allowLocalRoutees: allowLocalRoutees, //true if the node role is a Seed
                    useRole: "Seed"))
                    .Props(Props.Create(() => new CompanyDeliveryActor())), "company-router");

我有一个公司"类，该类是发送到路由器的消息所必需的.此测试的所有VolumeId均相同.

I have a "Company" class that is required for messages to the router. All VolumeIds are the same for this test.

public class Company
{
    public readonly Guid CompanyId;
    public readonly Guid VolumeId;
    public readonly string CompanyName;
    public Company(Guid companyId, Guid volumeId, string companyName)
    {
        this.CompanyId = companyId;
        this.VolumeId = volumeId;
        this.CompanyName = companyName;
    }
}

路由器映射所使用的IHasRouting接口:

The IHasRouting interface that is used by the router mapping:

public interface IHasRouting
{
    Company Company { get; }
}

可以发送到路由器的示例消息类:

An example message class that can be sent to the router:

public class GetTripsMessage : IHasRouting
{
    public Company Company { get; private set; }
    public GetTripsMessage(Company company)
    {
        this.Company = company;
    }
}

最后是在路由器上为每个路由实例化的CompanyDeliverActor:

And Finally the CompanyDeliverActor which is instantiated for each routee at the router:

public class CompanyDeliveryActor : ReceiveActor
{
    private readonly Dictionary<Guid, IActorRef> companyManagers = new Dictionary<Guid, IActorRef>();
    private readonly Guid instanceid = Guid.NewGuid();

    public CompanyDeliveryActor()
    {
        this.Receive<GetTripsMessage>(m => this.RouteCompanyMessage(m, m.Company));
        this.Receive<SetTripsMessage>(m => this.RouteCompanyMessage(m, m.Company));
    }

    private void RouteCompanyMessage(object m, Company company)
    {
        //placing a watch here shows that this.instanceid is different for messages from the client.

        if (!this.companyManagers.TryGetValue(company.CompanyId, out var manager))
        {
            manager = Context.ActorOf(Props.Create(() => new CompanyManagerActor()));
            this.companyManagers[company.CompanyId] = manager;                
        }

        manager.Tell(m, Context.Sender);
    }
}

感谢您的指导.

推荐答案

经过调查，我同意我对clustering-consistent-hash-router的理解是错误的.现在，我知道我需要将代表路由器的IActorRef与集群的其余部分进行通信.这可以通过ClusterSinglton或某种类型的分布式pub子机制来完成.一种机制需要处理以下情况:节点或Actor变得丢失"，实例化新的Actor(具有新的路由)，并将新的Actor传达给集群中具有先前引用的所有Actor.

After investigation I agree that my understanding of the clustered-consistent-hash-router is wrong. I now understand that I need to communicate the IActorRef that represents the router to the rest of the cluster. This might be accomplished via a ClusterSinglton or (possibly) a distributed pub sub mechanism of some type. A mechanism needs to handle the situation where the node or Actor becomes "lost", a new Actor (with new routees) is instantiated and the new Actor is communicated to all those in the cluster that had the previous reference.

我正在研究群集分片"方法，并将就该方法遇到的技术困难提出另一个问题.

I am investigating the Cluster Sharding approach and will post another question in regards to technical difficulties that I am having with that approach.

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