Increased timeout when syncing multiple blocks from 4s to 10s.

src/main/java/org/qortal/controller/Synchronizer.java

@@ -63,6 +63,9 @@ public class Synchronizer {
 	/* Minimum peer version that supports syncing multiple blocks at once via GetBlocksMessage */
 	private static final long PEER_VERSION_160 = 0x0100060000L;
 
+	/** Maximum time to wait for a peer to respond with blocks (ms) */
+	private static final int FETCH_BLOCKS_TIMEOUT = 10000;
+
 
 	private static Synchronizer instance;
 
@@ -1189,7 +1192,7 @@ public class Synchronizer {
 	private List<Block> fetchBlocks(Repository repository, Peer peer, byte[] parentSignature, int numberRequested) throws InterruptedException {
 		Message getBlocksMessage = new GetBlocksMessage(parentSignature, numberRequested);
 
-		Message message = peer.getResponse(getBlocksMessage);
+		Message message = peer.getResponseWithTimeout(getBlocksMessage, FETCH_BLOCKS_TIMEOUT);
 		if (message == null || message.getType() != MessageType.BLOCKS) {
 			return null;
 		}

src/main/java/org/qortal/network/Peer.java

@@ -538,18 +538,35 @@ public class Peer {
 	}
 
 	/**
-	 * Send message to peer and await response.
+	 * Send message to peer and await response, using default RESPONSE_TIMEOUT.
 	 * <p>
 	 * Message is assigned a random ID and sent. If a response with matching ID is received then it is returned to caller.
 	 * <p>
 	 * If no response with matching ID within timeout, or some other error/exception occurs, then return <code>null</code>.<br>
 	 * (Assume peer will be rapidly disconnected after this).
-	 * 
+	 *
 	 * @param message
 	 * @return <code>Message</code> if valid response received; <code>null</code> if not or error/exception occurs
 	 * @throws InterruptedException
 	 */
 	public Message getResponse(Message message) throws InterruptedException {
+		return getResponseWithTimeout(message, RESPONSE_TIMEOUT);
+	}
+
+	/**
+	 * Send message to peer and await response, using custom timeout.
+	 * <p>
+	 * Message is assigned a random ID and sent. If a response with matching ID is received then it is returned to caller.
+	 * <p>
+	 * If no response with matching ID within timeout, or some other error/exception occurs, then return <code>null</code>.<br>
+	 * (Assume peer will be rapidly disconnected after this).
+	 * 
+	 * @param message
+	 * @param timeout
+	 * @return <code>Message</code> if valid response received; <code>null</code> if not or error/exception occurs
+	 * @throws InterruptedException
+	 */
+	public Message getResponseWithTimeout(Message message, int timeout) throws InterruptedException {
 		BlockingQueue<Message> blockingQueue = new ArrayBlockingQueue<>(1);
 
 		// Assign random ID to this message
@@ -570,7 +587,7 @@ public class Peer {
 		}
 
 		try {
-			return blockingQueue.poll(RESPONSE_TIMEOUT, TimeUnit.MILLISECONDS);
+			return blockingQueue.poll(timeout, TimeUnit.MILLISECONDS);
 		} finally {
 			this.replyQueues.remove(id);
 		}