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Higher memory usage, blocked thread when using vertx circuit breaker

Context
I am getting high memory usage with the vertx circuit breaker. I am just using httpbin.org to get all success responses. For individual requests, it works fine. While running a load test the JVM old gen utilization is spiking up.
Reproducer
I have the main verticle code, pasting it here itself:
public class CleanServer extends AbstractVerticle {
Logger logger = Logger.getLogger(CleanServer.class.getName());
#Override
public void start(Promise<Void> startPromise) throws Exception {
Router router = Router.router(vertx);
CircuitBreakerCache cbc = new CircuitBreakerCache(vertx);
router.route(HttpMethod.GET, "/get").handler(context -> {
List<String> domains = context.queryParam("user");
String domain = domains.get(0);
CircuitBreaker cb = cbc.getCircuitBreaker(domain + context.request().path());
HttpServerResponse serverResponse =
context.response().setChunked(true);
cb.executeWithFallback(promise -> {
WebClientOptions options = new WebClientOptions().setTryUseCompression(true).setTcpNoDelay(true).setTcpCork(true).setReceiveBufferSize(128).setConnectTimeout(400);
WebClient client = WebClient.create(vertx, options);
client.get(80, "httpbin.org", "/status/200")
.timeout(2000)
.send(ar -> {
if (ar.succeeded()) {
HttpResponse<Buffer> response = ar.result();
int statusCode = response.statusCode();
if (statusCode != 200) {
promise.fail(response.statusMessage());
} else {
serverResponse.end("Hello!!");
promise.complete();
}
} else {
promise.fail(ar.cause().getMessage());
}
});
}, v -> {
// Executed when the circuit is opened
logger.log(Level.INFO, domain + " Failed " + cb.state().toString() + " Error: Circuit open");
serverResponse.setStatusCode(200).setStatusMessage("Circuit Open").end("Circuit Open");
return context;
});
});
// Create the HTTP server
vertx.createHttpServer(new HttpServerOptions().setMaxInitialLineLength(10000))
// Handle every request using the router
.requestHandler(router)
// Start listening
.listen(8080)
// Print the port
.onSuccess(server ->
System.out.println(
"HTTP server started on port " + server.actualPort()
)
);
}
}
Circuit breaker options:
CircuitBreakerOptions()
.setMaxFailures(50)
.setTimeout(5000)
.setFallbackOnFailure(true)
.setResetTimeout(10000)));
Steps to reproduce
API used: http://localhost:8080/get?user=abc
When I hit the above API at 50 QPS for 30 minutes. The java heap is getting filled up.
Extra
<vertx.version>4.2.6</vertx.version>
JVM params used:
-XX:+UseG1GC -Xms4g -Xmx4g -XX:InitiatingHeapOccupancyPercent=70 -XX:MaxGCPauseMillis=200 -XX:ParallelGCThreads=20 -XX:ConcGCThreads=5
JVM memory with the load test.
Error:
WARNING: Thread Thread[vert.x-eventloop-thread-3,5,main] has been blocked for 3050 ms, time limit is 2000 ms
I think I am blocking the thread somewhere but not sure where exactly as the code seems pretty simple as given in the documentation.

Is there any way to implement real time messaging web application (Push message to the client among multiple clients)? [duplicate]

I'm working on setting up my first websocket server for a communications app. I can't seem to figure out how websockets are implemented in Java.
I've tried, unsuccessfully, creating an annotation based Endpoint, but I'm not sure where the client info is going to come through. This is basically the gist of my code, without going into mundane details.
I'm trying to make the class MessageHelper deal with the websocket info transfer, I just can't grasp how to actually get the transfer there.
class MainServer implements Runnable {
// VARIABLES
ServerSocket serverSocket = null;
int port;
// CONSTRUCTORS
MainServer(int p) {
this.port = p;
}
// METHODS
public void run() {
openServerSocket();
while(!isStopped()){
try{
clientSocket = serverSocket.accept();
} catch(IOException e) {
// Do something
}
new Thread(new MainThread(clientSocket)).start();
}
}
}
// Other methods below.
public class MainThread {
final Socket socket;
MainThread(Socket s) {
this.socket = s;
}
public void run() {
try{
BufferedReader br = new BufferedReader(
new InputStreamReader(socket.getInputStream()));
String input = br.readLine(), read = br.readLine();
while(!input.isEmpty()) {
read += "\n";
read += input;
input = br.readLine();
}
/**
* Everything works fine, I'm just not sure where to go
* from here. I tried creating MessageHelper into the java
* websocket implementation using annotations but it did not
* accept input from the client after the handshake was
* made. My client would send something but it would just
* give and EOFException.
**/
if(websocketHandshakeRequest(read)) {
MessageHelper messageHelper =
new MessageHelper(this.socket);
} else {
// Do something
}
} catch(Exception e) {
// Do something.
}
}
}

Don't be confused about the name WebSocket. A TCP socket and a WebSocket are entirely different kind of "sockets".
In Java you use a ServerSocket for TCP sockets. TCP is a transport layer protocol used to implement application layer protocols like POP3 and HTTP.
WebSocket is a HTTP/1.1 protocol upgrade commonly used in web servers and web browsers. You cannot use a ServerSocket for the WebSocket protocol, at least not so straight forward as you might think. First, you have to implement the HTTP/1.1 protocol and then the WebSocket protocol on top of that.
In the Java world you can use web servers like Tomcat or Jetty which provide WebSocket implementations and a high level Java API. This API is part of the Jave Enterprise Edition (JEE). See also the Jave EE 7 Tutorial - Chapter 18 Java API for WebSocket.
E.g. Jetty is a lightweight JEE web server which can be embedded in your application or run as a stand-alone server. See Jetty Development Guide - Chapter 26. WebSocket Introduction.
So in a Java web application running in a WebSocket enabled JEE web server like Jetty you can implement a server side WebSocket as follows:
package com.example.websocket;
import org.apache.log4j.Logger;
import javax.websocket.CloseReason;
import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
#ServerEndpoint("/toUpper")
public class ToUpperWebsocket {
private static final Logger LOGGER = Logger.getLogger(ToUpperWebsocket.class);
#OnOpen
public void onOpen(Session session) {
LOGGER.debug(String.format("WebSocket opened: %s", session.getId()));
}
#OnMessage
public void onMessage(String txt, Session session) throws IOException {
LOGGER.debug(String.format("Message received: %s", txt));
session.getBasicRemote().sendText(txt.toUpperCase());
}
#OnClose
public void onClose(CloseReason reason, Session session) {
LOGGER.debug(String.format("Closing a WebSocket (%s) due to %s", session.getId(), reason.getReasonPhrase()));
}
#OnError
public void onError(Session session, Throwable t) {
LOGGER.error(String.format("Error in WebSocket session %s%n", session == null ? "null" : session.getId()), t);
}
}
You register your class as a WebSocket handler for the specific path with the #ServerEndpoint annotation. Your WebSocket URL is then ws://host:port/context/toUpper or wss://host:port/context/toUpper for HTTPS connections.
Edit:
Here is a very simplistic HTML page to demonstrate the client side connection to the above WebSocket. This page is served by the same webserver as the WebSocket. The webapplication containing the WebSocket is deployed at context "websocket" on localhost port 7777.
<html>
<body>
<h2>WebSocket Test</h2>
<div>
<input type="text" id="input" />
</div>
<div>
<input type="button" id="connectBtn" value="CONNECT" onclick="connect()" />
<input type="button" id="sendBtn" value="SEND" onclick="send()" disable="true" />
</div>
<div id="output">
<h2>Output</h2>
</div>
</body>
<script type="text/javascript">
var webSocket;
var output = document.getElementById("output");
var connectBtn = document.getElementById("connectBtn");
var sendBtn = document.getElementById("sendBtn");
var wsUrl = (location.protocol == "https:" ? "wss://" : "ws://") + location.hostname + (location.port ? ':'+location.port: '') + "/websocket/toUpper";
function connect() {
// open the connection if one does not exist
if (webSocket !== undefined
&& webSocket.readyState !== WebSocket.CLOSED) {
return;
}
updateOutput("Trying to establish a WebSocket connection to <code>" + wsUrl + "</code>");
// Create a websocket
webSocket = new WebSocket(wsUrl);
webSocket.onopen = function(event) {
updateOutput("Connected!");
connectBtn.disabled = true;
sendBtn.disabled = false;
};
webSocket.onmessage = function(event) {
updateOutput(event.data);
};
webSocket.onclose = function(event) {
updateOutput("Connection Closed");
connectBtn.disabled = false;
sendBtn.disabled = true;
};
}
function send() {
var text = document.getElementById("input").value;
webSocket.send(text);
}
function closeSocket() {
webSocket.close();
}
function updateOutput(text) {
output.innerHTML += "<br/>" + text;
}
</script>
</html>

If you're willing to use Java Spring - which I think would be great for your use case, it's pretty easy to setup a websocket server and client connection.
There's an example here - https://spring.io/guides/gs/messaging-stomp-websocket/

Error when communicating with the native messaging host from extension

I need to pass phonenumber from web page to desktop dialer. I have host, that catches phone number from page that passed from background.js:
var responseMessage = "";
chrome.runtime.onMessage.addListener(
function(request, sender, sendResponse) {
console.log(request.phonenumber);
chrome.runtime.sendNativeMessage('com.avvd.microsipcallfield', {text: request.phonenumber},function(response) {
if (chrome.runtime.lastError) {
responseMessage = chrome.runtime.lastError.message
console.log(responseMessage);
} else {
responseMessage = response;
}} )
sendResponse(responseMessage);
});
and sending it to host:
{
"name": "com.avvd.microsipcallfield",
"description": "Call Field Microsip host",
"path": "C:\\Users\\All Users\\callFieldHost\\host.bat",
"type": "stdio",
"allowed_origins": [
"chrome-extension://lbhgehbjeemkjmooaeopmfljahdoombd/"
]
}
Host.bat
java -jar HostDecoder.jar %*
in general, for the time being there is no host, there will be an application that opens an object from JSON and sends it to the dialer. However
I wrote simple recorder and this is an output:
1argument: chrome-extension://lbhgehbjeemkjmooaeopmfljahdoombd/
2argument: --parent-window=0
While i try to send number i get in console
"Error when communicating with the native messaging host." and how we can see there is no number passed to host listener.
Can somebody advice me to look for to repair this?

I resolve issue. Trouble was in absent #echo off in launcher.

Ok. There is another question. I try to read incoming messages but get stability zero size.
private String read(InputStream in) throws IOException {
byte[] length = new byte[4];
in.read(length);
int size = getInt(length);
if (size == 0) {
throw new InterruptedIOException("Zero size message");
}
byte[] message = new byte[size];
in.read(b);
return new String(message, "UTF-8");
}
private int getInt(byte[] bytes) {
return (bytes[3]<<24) & 0xff000000|
(bytes[2]<<16) & 0x00ff0000|
(bytes[1]<< 8) & 0x0000ff00|
(bytes[0]<< 0) & 0x000000ff;
}
I send with native message an object
{text: 4325345423}
What i miss in this case?

How to send message from node.js server to Android app?

Im trying to make a simple application. That is When I write a word at edittext in android app such as "Hi", Then android app send message "Hi" to node.js server and node.js server send message "Hi has sent successflly" to android app. This is just a example, actually my object is android send a data(message) to server, and receive another data(message) from server.
The problem is this. When I write a word at android app and press button, the message transmitted successfully(I can confirm by console at node.js). But I cant send message to android from node.js .. When I press send button, My android app shut down..
What android says is "java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.Activity.runOnUiThread(java.lang.Runnable)' on a null object reference" ..
Yesterday, this error didn't happened and another error occured. "cannot cast string to JSONObject."
I will show you my code.
Server Side(Node.js)
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);
var port = 12000;
app.get('/', function(req, res) {
res.sendFile('index.html');
})
io.on('connection', function(socket) {
console.log('Android device has been connected');
socket.on('message', function(data) {
console.log('message from Android : ' + data);
Object.keys(io.sockets.sockets);
Object.keys(io.sockets.sockets).forEach(function (id) {
console.log("ID : ", id );
io.to(id).emit('message', data);
console.log(data + ' has sent successfully');
})
/*if (data != null) {
io.emit('message', {message : data + ' has received successfully'});
}*/
})
socket.on('disconnect', function() {
console.log('Android device has been disconnected');
})
})
http.listen(port, function() {
console.log('Server Start at port number ' + port);
})
Client Side (Android)
private Emitter.Listener handleIncomingMessages = new Emitter.Listener(){
#Override
public void call(final Object... args){
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
JSONObject data = (JSONObject) args[0];
String message;
try {
message = data.getString("text").toString();
Log.i("result", message);
addMessage(message);
} catch (JSONException e) {
Log.e("result", "Error : JSONException");
return;
} catch (ClassCastException e) {
Log.e("result", "Error : ClassCastException");
e.printStackTrace();
return;
}
}
});
}
};
private void sendMessage(){
String message = mInputMessageView.getText().toString().trim();
mInputMessageView.setText("");
addMessage(message);
JSONObject sendText = new JSONObject();
try{
sendText.put("text", message);
socket.emit("message", message);
}catch(JSONException e){
}
}
private void addMessage(String message) {
mMessages.add(new Message.Builder(Message.TYPE_MESSAGE)
.message(message).build());
// mAdapter = new MessageAdapter(mMessages);
mAdapter = new MessageAdapter( mMessages);
mAdapter.notifyItemInserted(0);
scrollToBottom();
}
private void scrollToBottom() {
mMessagesView.scrollToPosition(mAdapter.getItemCount() - 1);
}
I already searched similar problems that other people asked, but It didn't give me solution. Please help me. Thank you for reading long question.
p.s Because Im not English speaker, Im not good at English .. There will be many problems at grammar and writing skills. Thanks for understanding...

Reason this happens is because method getActivity() returns null. This might happen if you run this on a fragment after it is detached from an activity or activity is no longer visible. I would do a normal null check before like:
Activity activity = getActivity();
if(activity != null) {
activity.runOnUiThread(new Runnable() {...}
}
I'm not familiar with socket.emit() method but it might throw network exception since it's running on UI thread and you are not allowed to do that. I recommend using RxJava/RxAndroid if you want to do this on another thread.
If you want to do network operation just use it like this:
Observable
.fromRunnable(new Runnable {
void run() {
// here do your work
}
})
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Subscriber<Void>() {
#Override
public void onCompleted() {
// not really needed here
}
#Override
public void onError(Throwable e) {
// handle errors on UI thread
}
#Override
public void onNext(Void void) {
// do something on UI thread after run is done
}
});
Basically what it does it calls method call from Callable you just made on separate thread and when it's over it invokes onNext method if no exception was thrown or onError method if exception was thrown from Subscriber class.
Note that Response class isn't part of the RxJava/RxAndroid API and you can make it if you want. You can make it a simple POJO class or anything else you need it to be. If you don't need to have response you can use Runnable instead of Callable and it will work just fine.
In order for this to work you need to add this dependencies to your modules Gradle file:
dependencies {
compile 'io.reactivex:rxandroid:1.2.1'
compile 'io.reactivex:rxjava:1.1.6'
}

How to define Spring WebSocket subscriber path

I want to know how to define the subscriber path.
For instance, declaration of subscribing path
stompClient.subscribe("/topic/simplemessagesresponse", function(servermessage) {
Why there are two parts 'topic' and 'simplemessageresponse' .. what they refere. How many such domain parts can be there and why ? My question is on not only for the client side, but also server side . SimpMessagingTemplate.convertAndSend("/topic/simplemessagesresponse", "Message to client");
There are tutorials showing the websocket server and client samples. But no enough details of rules to declare the subscriber path and how the subscriber path could be found.
What are the dependencies to change the path when it is declared in server and client side. I think another similar question is raised because of the a location change of a page where the websocket client is written.

Quoting the STOMP spec documentation:
Note that STOMP treats this destination as an opaque string and no
delivery semantics are assumed by the name of a destination. You
should consult your STOMP server's documentation to find out how to
construct a destination name which gives you the delivery semantics
that your application needs.
That means that destination semantics is broker specific:
For RabbitMQ: check out the Destinations section under the STOMP
plugin documentation- http://www.rabbitmq.com/stomp.html For
For ActiveMQ: check out the Working with Destinations with Stomp -
https://activemq.apache.org/stomp.html

I have implemented the websocket stomp by following this blog.
I replaced #SendTo by SimpMessagingTemplate.
Here is my sample ChatController
#Autowired
private SimpMessagingTemplate simpMessagingTemplate;
#MessageMapping("/dualchart")
#ResponseBody
public void dualchat(MessageDTO message) {
// forward message to destination
String destination = "/topic/dualchat/" + message.getToUser();
simpMessagingTemplate.convertAndSend(destination, message);
}
MessageDTO
#JsonIgnoreProperties
public class MessageDTO extends BaseModel {
private String fromUser;
private String toUser;
private String message;
public String getFromUser() {
return fromUser;
}
public void setFromUser(String fromUser) {
this.fromUser = fromUser;
}
public String getToUser() {
return toUser;
}
public void setToUser(String toUser) {
this.toUser = toUser;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
Web Socket Config
<websocket:message-broker application-destination-prefix="/app">
<websocket:stomp-endpoint path="/dualchat">
<websocket:sockjs />
</websocket:stomp-endpoint>
<websocket:simple-broker prefix="/topic" />
</websocket:message-broker>
Javascript
var socket = new SockJS("/starter.web.admin/dualchat");
var stompClient = Stomp.over(page.socket);
stompClient.connect({}, socketJsConnectedCallback, socketJsErrorCallback);
function socketJsConnectedCallback() {
var myId = "111"; // replace this Id
stompClient.subscribe('/topic/dualchat/' + myId, function(message) {
console.log("you reveived a message::::::::::" + JSON.stringify(message));
// you have message, and you can do anything with it
});
}
function socketJsErrorCallback(error){console.log(error);}
function sendMessage(message) {
var data = {
toUser : "1",
message : message
}
stompClient.send("/app/dualchat", {}, JSON.stringify(data );
}
Hope this will help next search...