Actor 模型在处理并发内存状态时是否最有效？

import akka.actor.typed.{ActorRef, Behavior}
import akka.actor.typed.scaladsl.{AbstractBehavior, ActorContext, Behaviors}
import akka.cluster.sharding.typed.scaladsl.{ClusterSharding, Entity, EntityTypeKey}
import akka.persistence.typed.PersistenceContext
import akka.persistence.typed.scaladsl.{Effect, EventSourcedBehavior, ReplyEffect}

object AggregateActor {

  // Commands
  sealed trait Command
  final case class ProcessCommand(data: String, replyTo: ActorRef[Response]) extends Command
  final case class GetState(replyTo: ActorRef[State]) extends Command

  // Events
  sealed trait Event
  final case class CommandProcessed(data: String) extends Event

  // State
  final case class State(data: String)

  // Responses
  sealed trait Response
  final case class CommandAccepted(newState: State) extends Response
  final case object CommandRejected extends Response

  // Actor Behavior
  def apply(aggregateId: String): Behavior[Command] =
    Behaviors.setup(context => new AggregateActor(context, aggregateId).eventSourcedBehavior())
}

class AggregateActor(context: ActorContext[AggregateActor.Command], aggregateId: String) {
  import AggregateActor._

  val persistenceId: String = s"aggregate-$aggregateId"

  def eventSourcedBehavior(): EventSourcedBehavior[Command, Event, State] =
    EventSourcedBehavior[Command, Event, State](
      persistenceId = persistenceId,
      emptyState = State(""),
      commandHandler = (state, command) =>
        command match {
          case ProcessCommand(data, replyTo) =>
            Effect
              .persist(CommandProcessed(data))
              .thenReply(replyTo)(newState => CommandAccepted(newState))
          case GetState(replyTo) =>
            Effect.reply(replyTo)(state)
        },
      eventHandler = (state, event) =>
        event match {
          case CommandProcessed(data) =>
            State(data)
        }
    )
}

// Example Usage (Cluster Sharding)
object ExampleUsage {
  import AggregateActor._
  import akka.actor.typed.ActorSystem

  def main(args: Array[String]): Unit = {
    implicit val system: ActorSystem[Nothing] = ActorSystem(Behaviors.empty, "MySystem")

    val sharding = ClusterSharding(system)

    val typeKey: EntityTypeKey[Command] = EntityTypeKey[Command]("Aggregate")

    sharding.init(Entity(typeKey) { entityContext =>
      AggregateActor(entityContext.entityId)
    })

    val aggregateRef: ActorRef[Command] = sharding.entityRefFor(typeKey, "aggregate-1")

    import akka.util.Timeout
    import scala.concurrent.duration._
    import akka.actor.typed.scaladsl.AskPattern._

    implicit val timeout: Timeout = Timeout(5.seconds)

    import scala.concurrent.ExecutionContext.Implicits.global

    aggregateRef.ask(replyTo => ProcessCommand("New Data", replyTo)).onComplete {
      case scala.util.Success(CommandAccepted(newState)) =>
        println(s"Command Accepted, New State: $newState")
      case scala.util.Failure(ex) =>
        println(s"Command Rejected: ${ex.getMessage}")
    }
  }
}