Question

我在AWS ECS上测试akka http服务。每个实例都添加到负载均衡器，负载均衡器定期向健康检查路由发出请求。由于这是一个测试环境，我可以控制没有其他流量进入服务器。我注意到调试日志表明＆＃34;默认调度程序＆＃34;数字一直在增加：

[DEBUG] [01/03/2017 22:33:03.007] [default-akka.actor.default-dispatcher-41200] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted
[DEBUG] [01/03/2017 22:33:29.142] [default-akka.actor.default-dispatcher-41196] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted
[DEBUG] [01/03/2017 22:33:33.035] [default-akka.actor.default-dispatcher-41204] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted
[DEBUG] [01/03/2017 22:33:59.174] [default-akka.actor.default-dispatcher-41187] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted
[DEBUG] [01/03/2017 22:34:03.066] [default-akka.actor.default-dispatcher-41186] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted
[DEBUG] [01/03/2017 22:34:29.204] [default-akka.actor.default-dispatcher-41179] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted
[DEBUG] [01/03/2017 22:34:33.097] [default-akka.actor.default-dispatcher-41210] [akka://default/system/IO-TCP/selectors/$a/0] New connection accepted

这种趋势永远不会逆转，很快就会上升到成千上万。这是正常行为还是表明存在问题？

修改：我已更新日志片段，以显示调度程序的广告编号超出了我的预期。

编辑＃2：以下是运行状况检查路径代码：

class HealthCheckRoutes()(implicit executionContext: ExecutionContext)
  extends LogHelper {

  val routes = pathPrefix("health-check") {
    pathEndOrSingleSlash {
      complete(OK -> "Ok")
    }
  }
}

Answer 1

可能，是的。我认为那是线程名称。

如果您在服务器上执行a thread dump，它是否有很多开放线程？

看起来您的服务器每个连接泄漏一个线程。

（在开发机器上调试和诊断它可能要容易得多，而不是在EC2 VM上。尝试在本地重现它。）

Answer 2

根据此akka-http github问题，似乎没有问题：https://github.com/akka/akka-http/issues/722

Answer 3

对于你的问题，请查看此评论：

Akka http server dispatcher number constantly increasing

关于调度员：

将默认调度程序用于健康检查等操作是没有问题的。

线程由您指定的调度程序控制，如果未指定，则由 default-dispatcher 控制。 default-dispatcher 设置如下，这意味着线程池大小介于8到64之间或等于（处理器数* 3）

default-dispatcher {
  type = "Dispatcher"

  executor = "default-executor"

  default-executor {
    fallback = "fork-join-executor"
  }

  fork-join-executor {
    # Min number of threads to cap factor-based parallelism number to
    parallelism-min = 8

    # The parallelism factor is used to determine thread pool size using the
    # following formula: ceil(available processors * factor). Resulting size
    # is then bounded by the parallelism-min and parallelism-max values.
    parallelism-factor = 3.0

    # Max number of threads to cap factor-based parallelism number to
    parallelism-max = 64

    # Setting to "FIFO" to use queue like peeking mode which "poll" or "LIFO" to use stack
    # like peeking mode which "pop".
    task-peeking-mode = "FIFO"
  }

Dispathcer文件： http://doc.akka.io/docs/akka/2.4.16/scala/dispatchers.html

配置参考： http://doc.akka.io/docs/akka/2.4.16/general/configuration.html#akka-actor

BTW操作需要很长时间并阻止其他操作，下面是如何在Akka HTTP中为它们指定自定义调度程序： http://doc.akka.io/docs/akka-http/current/scala/http/handling-blocking-operations-in-akka-http-routes.html

Akka http服务器调度员号码不断增加

3 个答案: