perf(net): optimize the k-bucket data structure to improve performance

Author: xxo1shine

framework/src/main/java/org/tron/common/overlay/discover/table/NodeTable.java

@@ -20,7 +20,10 @@
 
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
+
 import lombok.extern.slf4j.Slf4j;
 import org.tron.common.overlay.discover.node.Node;
 
@@ -29,7 +32,7 @@ public class NodeTable {
 
   private final Node node;  // our node
   private transient NodeBucket[] buckets;
-  private transient List<NodeEntry> nodes;
+  private transient Map<String, NodeEntry> nodes;
 
   public NodeTable(Node n) {
     this.node = n;
@@ -41,15 +44,19 @@ public Node getNode() {
   }
 
   public final void initialize() {
-    nodes = new ArrayList<>();
+    nodes = new HashMap<>();
     buckets = new NodeBucket[KademliaOptions.BINS];
     for (int i = 0; i < KademliaOptions.BINS; i++) {
       buckets[i] = new NodeBucket(i);
     }
   }
 
   public synchronized Node addNode(Node n) {
-    NodeEntry entry = getNodeEntry(n);
+    if (n.getHost().equals(node.getHost())) {
+      return null;
+    }
+
+    NodeEntry entry = nodes.get(n.getHost());
     if (entry != null) {
       entry.touch();
       return null;
@@ -60,24 +67,24 @@ public synchronized Node addNode(Node n) {
     if (lastSeen != null) {
       return lastSeen.getNode();
     }
-    nodes.add(e);
+    nodes.put(n.getHost(), e);
     return null;
   }
 
   public synchronized void dropNode(Node n) {
-    NodeEntry entry = getNodeEntry(n);
+    NodeEntry entry = nodes.get(n.getHost());
     if (entry != null) {
       nodes.remove(entry);
       buckets[getBucketId(entry)].dropNode(entry);
     }
   }
 
   public synchronized boolean contains(Node n) {
-    return getNodeEntry(n) != null;
+    return nodes.containsKey(n.getHost());
   }
 
   public synchronized void touchNode(Node n) {
-    NodeEntry entry = getNodeEntry(n);
+    NodeEntry entry = nodes.get(n.getHost());
     if (entry != null) {
       entry.touch();
     }
@@ -103,9 +110,7 @@ public synchronized int getNodesCount() {
   }
 
   public synchronized List<NodeEntry> getAllNodes() {
-    List<NodeEntry> list = new ArrayList<>(nodes);
-    list.remove(new NodeEntry(node.getId(), node));
-    return list;
+    return new ArrayList<>(nodes.values());
   }
 
   public synchronized List<Node> getClosestNodes(byte[] targetId) {
@@ -123,14 +128,4 @@ public synchronized List<Node> getClosestNodes(byte[] targetId) {
     return closestNodes;
   }
 
-  private NodeEntry getNodeEntry(Node n) {
-    NodeEntry entry = null;
-    for (NodeEntry e: nodes) {
-      if (e.getNode().getHost().equals(n.getHost())) {
-        entry = e;
-        break;
-      }
-    }
-    return entry;
-  }
 }