ZMX #78 Optimization

docker-compose.yml

@@ -10,13 +10,14 @@ services:
     stdin_open: true
     tty: true
     networks:
-      - onion-network
+      onion-network:
+        ipv4_address: 10.12.137.21
 
   config-node:
     build: .
     container_name: config-node
     environment:
-      - BOOTSTRAP_HOST=bootstrap-node
+      - BOOTSTRAP_HOST=10.12.137.21
       - NODE_PORT=12128
     ports:
       - "12128:12128"
@@ -30,7 +31,7 @@ services:
   peer:
     build: .
     environment:
-      - BOOTSTRAP_HOST=bootstrap-node
+      - BOOTSTRAP_HOST=10.12.137.21
     depends_on:
       - bootstrap-node
     stdin_open: true
@@ -40,4 +41,8 @@ services:
 
 networks:
   onion-network:
-    driver: bridge
+    driver: bridge
+    ipam:
+      config:
+        - subnet: 10.12.137.0/24
+          gateway: 10.12.137.1

src/main/java/dev/network/NetworkManager.java

@@ -98,8 +98,9 @@ public void registerPeer(Peer peer) {
 
         if (getConnectedPeerCount() >= config.getMaxConnections()) {
             logger.warn("Max peers reached. Cannot register new peer: {}", peer.getPeerId());
-            Collections.shuffle(getKnownPeers());
-            peer.send(MessageBuilder.buildPeerResponseMessage(getKnownPeers().stream().limit(5).toList()));
+            List<PeerInfo> sample = new ArrayList<>(getKnownPeers());
+            Collections.shuffle(sample);
+            peer.send(MessageBuilder.buildPeerResponseMessage(sample.stream().limit(config.getMinConnections()).toList()));
             peer.disconnect();
             return;
         }
@@ -118,40 +119,50 @@ public void startPeerMaintenance() {
         logger.info("   >-->   Connected: {} | Known: {}   <--<", getConnectedPeers().size(), getKnownPeers().size());
         if (getConnectedPeerCount() >= config.getMaxConnections()) return;
 
-        List<PeerInfo> candidates = new ArrayList<>(knownPeers
-                .stream()
-                .filter(peer -> !connectedPeers
-                        .containsKey(peer.getPublicKey()) && !peer.getPublicKey()
-                        .equals(encodedPublicKey))
-                .toList());
+        if (!config.isBootstrapNode() && getConnectedPeerCount() == 0) {
+            logger.info("Isolated peer. Retrying bootstrap on {}:{}", config.getBootstrapNodeHost(), config.getBootstrapNodePort());
+            peerExecutor.submit(() -> connectToPeer(config.getBootstrapNodeHost(), config.getBootstrapNodePort()));
+            return;
+        }
+
+        int targetConnections = config.getMinConnections();
+        int missing = targetConnections - getConnectedPeerCount();
+        if (missing <= 0) return;
+
+        List<PeerInfo> candidates = new ArrayList<>(getKnownPeers());
+
+        candidates.removeIf(peer ->
+                connectedPeers.containsKey(peer.getPublicKey()) ||
+                        peer.getPublicKey().equals(encodedPublicKey));
 
         Collections.shuffle(candidates);
 
-        for (PeerInfo info : candidates) {
-            logger.info("Trying to connect to peer: {}:{}", info.host, info.port);
-            if (connectedPeers.size() > config.getMaxConnections()) break;
+        for (PeerInfo info : candidates.stream().limit(missing).toList()) {
             peerExecutor.submit(() -> connectToPeer(info.host, info.port));
         }
     }
 
+    // GPT helper understand the exponential back-off, specifically how to define timeout interval
     public void connectToPeer(String ip, int port) {
+        logger.info("Trying to connect to peer: {}:{}", ip, port);
         int attempts = config.getConnectionRetryAttempts();
-        int retries = 0;
-        while (retries++ < attempts) {
+
+        for (int retries = 1; retries < attempts; retries++) {
             try {
                 Socket socket = new Socket();
                 socket.connect(new InetSocketAddress(ip, port), config.getConnectionTimeoutInMilliseconds());
                 logger.info("Connected to node: {}", socket.getRemoteSocketAddress());
                 peerExecutor.submit(new Peer(socket, queue, this, PeerDirection.OUTBOUND));
                 return;
             } catch (IOException e) {
+//                if (retries == attempts) break;
+                long timeout = (1L << (retries - 1)) * 100;
+                logger.warn(e, "Failed connecting to {}:{} (attempt {}/{}). Retrying in {}ms...", ip, port, retries, attempts, timeout);
                 try {
-                    long timeout = (1L << (retries - 1)) * 100;
-                    logger.warn("Failed connecting to {}:{} (attempt {}/{}). Retrying in {}ms...", ip, port, retries, attempts, timeout);
-                    if (retries == attempts) continue;
                     Thread.sleep(timeout);
                 } catch (InterruptedException ex) {
                     logger.error("Interrupted while waiting for outbound node.", ex);
+//                    Thread.currentThread().interrupt(); // figure out why
                     return;
                 }
             }

src/main/java/dev/network/Server.java

@@ -10,6 +10,7 @@
 import java.net.ServerSocket;
 import java.net.Socket;
 import java.util.concurrent.ExecutorService;
+import java.util.concurrent.ThreadLocalRandom;
 
 public class Server extends Thread {
     private final Logger logger;
@@ -30,16 +31,18 @@ public Server(Config config, MessageQueue queue, NetworkManager networkManager,
 
     @Override
     public void run() {
-        try (ServerSocket serverSocket = new ServerSocket(config.getNodePort())) {
+        int backlog = config.getMaxConnections();
+        try (ServerSocket serverSocket = new ServerSocket(config.getNodePort(), backlog)) {
             logger.info("Server started and waiting for connections on port " + config.getNodePort());
             if (!config.isBootstrapNode()) peerExecutor.submit(this::connectToBootstrapNodes);
 
             while (!this.isInterrupted()) {
                 Socket clientSocket = serverSocket.accept();
-                logger.info("======= New connection: =======");
-                logger.info("  -> Remote IP:   " + clientSocket.getInetAddress().getHostAddress());
-                logger.info("  -> Remote Port: " + clientSocket.getPort());
-                logger.info("===============================");
+                logger.info("""
+                        =========== New connection: ===========
+                         -> Remote IP: {}:{}
+                        =======================================
+                        """,  clientSocket.getInetAddress().getHostAddress(), clientSocket.getPort());
                 peerExecutor.submit(new Peer(clientSocket, queue, networkManager, PeerDirection.INBOUND));
             }
         } catch (BindException e) {
@@ -54,6 +57,12 @@ public void run() {
     }
 
     private void connectToBootstrapNodes() {
+        try {
+            Thread.sleep(ThreadLocalRandom.current().nextInt(0, 1000 * 30));
+        } catch (InterruptedException e) {
+            logger.alert(e, "Connection initialization cooldown timeout interrupted...");
+        }
+
         logger.info("Connecting to the bootstrap node at {}:{}", config.getBootstrapNodeHost(), config.getBootstrapNodePort());
         networkManager.connectToPeer(config.getBootstrapNodeHost(), config.getBootstrapNodePort());
     }

src/main/resources/node.bootstrap.properties

@@ -2,7 +2,7 @@ node.port=12137
 node.bootstrap=true
 
 node.connections.max=100
-node.connections.min=3
+node.connections.min=10
 
 peer.discovery.init=5
 peer.discovery.delay=30

src/main/resources/node.peer.properties

@@ -2,7 +2,7 @@ node.port=12138
 node.bootstrap=false
 
 node.connections.max=100
-node.connections.min=3
+node.connections.min=10
 
 peer.discovery.init=5
 peer.discovery.delay=30

src/main/resources/node.peer.test1.properties

@@ -1,8 +1,8 @@
 node.port=12141
 node.bootstrap=false
 
-node.connections.max=5
-node.connections.min=3
+node.connections.max=15
+node.connections.min=10
 
 peer.discovery.init=5
 peer.discovery.delay=30

src/main/resources/node.peer.test2.properties

@@ -1,8 +1,8 @@
 node.port=12142
 node.bootstrap=false
 
-node.connections.max=5
-node.connections.min=3
+node.connections.max=15
+node.connections.min=10
 
 peer.discovery.init=5
 peer.discovery.delay=30

src/main/resources/node.peer.test3.properties

@@ -1,8 +1,8 @@
 node.port=12143
 node.bootstrap=false
 
-node.connections.max=5
-node.connections.min=3
+node.connections.max=15
+node.connections.min=10
 
 peer.discovery.init=5
 peer.discovery.delay=30