Bugfix in Bittorrent example

diff --git a/examples/bittorrent/Common.java b/examples/bittorrent/Common.java
index 51cb01d..e69d3c8 100644 (file)
--- a/examples/bittorrent/Common.java
+++ b/examples/bittorrent/Common.java
@@ -3,6 +3,7 @@ package bittorrent;
  * Common constants for use in the simulation
  */
 public class Common {  
+               
        public static String TRACKER_MAILBOX = "tracker_mailbox";
        
        public static int FILE_SIZE = 5120;
@@ -48,7 +49,7 @@ public class Common {
        /**
         * Interval between each update of the choked peers
         */
-       public static int UPDATE_CHOKED_INTERVAL = 50;
+       public static int UPDATE_CHOKED_INTERVAL = 30;
        /**
         * Number of pieces the peer asks for simultaneously
         */

diff --git a/examples/bittorrent/Connection.java b/examples/bittorrent/Connection.java
index 5cb1b62..87ecacc 100644 (file)
--- a/examples/bittorrent/Connection.java
+++ b/examples/bittorrent/Connection.java
@@ -1,7 +1,7 @@
 package bittorrent;
 
 import java.util.Arrays;
-
+import org.simgrid.msg.Msg;
 public class Connection {
        /**
         * Remote peer id
@@ -31,7 +31,18 @@ public class Connection {
         * Indicates if the peer has choked the current peer
         */
        public boolean chokedDownload = true;
-       
+       /**
+        * Number of messages we have received from the peer
+        */
+       public int messagesCount = 0;
+       /**
+        * Peer speed.
+        */
+       public double peerSpeed = 0;
+       /**
+        * Last time the peer was unchoked
+        */
+       public double lastUnchoke = 0;
        /**
         * Constructor
         */
@@ -39,7 +50,14 @@ public class Connection {
                this.id = id;
                this.mailbox = Integer.toString(id);
        }
-
+       /**
+        * Add a new value to the peer speed average
+        */
+       public void addSpeedValue(double speed) {
+               peerSpeed = peerSpeed * 0.55 + speed * 0.45;
+               //              peerSpeed = (peerSpeed * messagesCount + speed) / (++messagesCount);            
+       }
+               
        @Override
        public String toString() {
                return "Connection [id=" + id + ", bitfield="

diff --git a/examples/bittorrent/Peer.java b/examples/bittorrent/Peer.java
index 68c694e..981596d 100644 (file)
--- a/examples/bittorrent/Peer.java
+++ b/examples/bittorrent/Peer.java
@@ -2,6 +2,7 @@ package bittorrent;
 
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.Map.Entry;
 
@@ -13,12 +14,15 @@ import org.simgrid.msg.RngStream;
 import org.simgrid.msg.Process;
 import org.simgrid.msg.Task;
 
+import bittorrent.Connection;
+
 /**
  * Main class for peers execution
  */
 public class Peer extends Process {
        protected int round = 0;
        
+       protected double beginReceiveTime;
        protected double deadline;
        
        protected static RngStream stream = new RngStream();
@@ -70,6 +74,7 @@ public class Peer extends Process {
                if (getPeersData()) {
                        Msg.debug("Got " + peers.size() + " peers from the tracker");
                        Msg.debug("Here is my current status: " + getStatus());
+                       beginReceiveTime = Msg.getClock();                      
                        if (hasFinished()) {
                                pieces = Common.FILE_PIECES;
                                sendHandshakeAll();
@@ -351,6 +356,10 @@ public class Peer extends Process {
                                }
                        break;
                }
+               if (remotePeer != null) {
+                       remotePeer.addSpeedValue(1 / (Msg.getClock() - beginReceiveTime));
+               }
+               beginReceiveTime = Msg.getClock();
        }
        /**
         * Wait for the node to receive interesting bitfield messages (ie: non empty)
@@ -439,33 +448,57 @@ public class Peer extends Process {
                        peerChoked.chokedUpload = true;
                        activePeers.remove(e.getKey());
                }
-               //Random optimistic unchoking
-               if (round == 0 || true) {
-                       int j = 0, i;
-                       Connection peerChoosed = null;
-                       do {
-                               i = 0;
-                               int idChosen = stream.randInt(0,peers.size() - 1);
-                               for (Connection connection : peers.values()) {
-                                       if (i == idChosen) {
-                                               peerChoosed = connection;
-                                               break;
+               Connection peerChoosed = null;
+               //Separate the case from when the peer is seeding.
+               if (pieces == Common.FILE_PIECES) {
+                       //Find the last unchoked peer.
+                       double unchokeTime = deadline + 1;
+                       for (Connection connection : peers.values()) {
+                               if (connection.lastUnchoke < unchokeTime && connection.chokedUpload && connection.interested) {
+                                       peerChoosed = connection;
+                                       unchokeTime = connection.lastUnchoke;
+                               }
+                       }
+               }
+               else {
+                       //Random optimistic unchoking
+                       if (round == 0) {
+                               int j = 0, i;
+                               do {
+                                       i = 0;
+                                       int idChosen = stream.randInt(0,peers.size() - 1);
+                                       for (Connection connection : peers.values()) {
+                                               if (i == idChosen) {
+                                                       peerChoosed = connection;
+                                                       break;
+                                               }
+                                               i++;
+                                       } //TODO: Not really the best way ever
+                                       if (!peerChoosed.interested) {
+                                               peerChoosed = null;
+                                       }
+                                       j++;
+                               } while (peerChoosed == null && j < 
+       Common.MAXIMUM_PEERS);
+                       }
+                       else {
+                               Connection fastest = null;
+                               double fastestSpeed = 0;
+                               for (Connection c : peers.values()) {
+                                       if (c.peerSpeed > fastestSpeed && c.chokedUpload && c.interested) {
+                                               fastest = c;
+                                               fastestSpeed = c.peerSpeed;
                                        }
-                                       i++;
-                               } //TODO: Not really the best way ever
-                               if (!peerChoosed.interested) {
-                                       peerChoosed = null;
                                }
-                               j++;
-                       } while (peerChoosed == null && j < 
-Common.MAXIMUM_PEERS);
-                       if (peerChoosed != null) {
-                               activePeers.put(peerChoosed.id,peerChoosed);
-                               peerChoosed.chokedUpload = false;
-                               sendUnchoked(peerChoosed.mailbox);
+                               peerChoosed = fastest;
                        }
                }
-               //TODO: Use the leecher choke algorithm.
+               if (peerChoosed != null) {
+                       activePeers.put(peerChoosed.id,peerChoosed);
+                       peerChoosed.chokedUpload = false;
+                       peerChoosed.lastUnchoke = Msg.getClock();
+                       sendUnchoked(peerChoosed.mailbox);
+               }
        }
        /**     
         * Updates our "interested" state about peers: send "not interested" to peers

diff --git a/examples/kademlia/Node.java b/examples/kademlia/Node.java
index e8e4e70..1655a7d 100644 (file)
--- a/examples/kademlia/Node.java
+++ b/examples/kademlia/Node.java
@@ -257,7 +257,7 @@ public class Node extends Process {
                return destinationFound;
        }
        /**
-        * Sends a "PING" request to a node
+        * Sends a "PING" reque ast to a node
         * @param destination Ping destination id.
         */
        public void ping(int destination) {