When the NUMBER of TCP connections exceeds the number of logical cores, it is always in a waiting state

[BornToRain]

Questions

I have some old project code that uses tcp, and I want to use vertx-tcp to proxy them.

I use tcp server and client as a Proxy,tcp-server is running at 8080,tcp-client is running at random port.

when set the verticle instance number greater than or equal to logical cpu number,tcp connection is always waiting.

In my environment, the number is 12, when set the TestVerticle instance number < 12,it can proxy tcp.

Version

vertx-lang-scala_2.12:3.9.1

Code snippet

class TestVerticle extends ScalaVerticle {
  private[this] lazy val proxy = vertx.createNetServer
  // 60000-65535
  private[this] lazy val randomPort = Random.nextInt(5536) + 60000
  override def startFuture() = {
    proxy.connectHandler { proxy =>
      log.info(s"0.0.0.0:${randomPort} create connection")
      vertx.createNetClient.connectFuture(randomPort, "0.0.0.0").map { client =>
        log.info("proxy connect success")
        Pump.pump(proxy, client).start
        Pump.pump(client, proxy).start
      }
      proxy.closeHandler(_ => log.info("0.0.0.0:${randomPort} disconnect connection"))
    }
    proxy.listenFuture(8080)
  }
  override def stop(): Unit = proxy.close(_ => log.info(s"proxy disconnect connection"))
}

Extra

• OS macOs Catalina 10.15.6 2.6GHz 6 physical cpu
• java 11.0.7
• graal vm ce 20.1.0

[vietj]

@BornToRain can you share a similar projects in Java that we can run to reproduce the issue ?