コード例 #1
0
ファイル: UNICAST2.java プロジェクト: pulasthi/JGroups
  /**
   * Check whether the hashtable contains an entry e for <code>sender</code> (create if not). If
   * e.received_msgs is null and <code>first</code> is true: create a new AckReceiverWindow(seqno)
   * and add message. Set e.received_msgs to the new window. Else just add the message.
   */
  protected void handleDataReceived(
      Address sender, long seqno, short conn_id, boolean first, Message msg, Event evt) {
    if (log.isTraceEnabled()) {
      StringBuilder sb = new StringBuilder();
      sb.append(local_addr).append(" <-- DATA(").append(sender).append(": #").append(seqno);
      if (conn_id != 0) sb.append(", conn_id=").append(conn_id);
      if (first) sb.append(", first");
      sb.append(')');
      log.trace(sb);
    }

    ReceiverEntry entry;
    NakReceiverWindow win;

    recv_table_lock.lock();
    try {
      entry = recv_table.get(sender);
      win = entry != null ? entry.received_msgs : null;
      if (first) {
        if (entry == null) {
          entry = getOrCreateReceiverEntry(sender, seqno, conn_id);
          win = entry.received_msgs;
        } else { // entry != null && win != null
          if (conn_id != entry.recv_conn_id) {
            if (log.isTraceEnabled())
              log.trace(
                  local_addr
                      + ": conn_id="
                      + conn_id
                      + " != "
                      + entry.recv_conn_id
                      + "; resetting receiver window");

            ReceiverEntry entry2 = recv_table.remove(sender);
            if (entry2 != null) entry2.received_msgs.destroy();

            entry = getOrCreateReceiverEntry(sender, seqno, conn_id);
            win = entry.received_msgs;
          } else {;
          }
        }
      } else { // entry == null && win == null OR entry != null && win == null OR entry != null &&
               // win != null
        if (win == null || entry.recv_conn_id != conn_id) {
          recv_table_lock.unlock();
          sendRequestForFirstSeqno(sender, seqno); // drops the message and returns (see below)
          return;
        }
      }
    } finally {
      if (recv_table_lock.isHeldByCurrentThread()) recv_table_lock.unlock();
    }

    entry.update();
    boolean added = win.add(seqno, msg); // win is guaranteed to be non-null if we get here
    num_msgs_received++;
    num_bytes_received += msg.getLength();

    if (added) {
      int len = msg.getLength();
      if (len > 0) {
        boolean send_stable_msg = false;
        entry.lock();
        try {
          entry.received_bytes += len;
          if (entry.received_bytes >= max_bytes) {
            entry.received_bytes = 0;
            send_stable_msg = true;
          }
        } finally {
          entry.unlock();
        }

        if (send_stable_msg)
          sendStableMessage(
              sender, entry.recv_conn_id, win.getHighestDelivered(), win.getHighestReceived());
      }
    }

    // An OOB message is passed up immediately. Later, when remove() is called, we discard it. This
    // affects ordering !
    // http://jira.jboss.com/jira/browse/JGRP-377
    if (msg.isFlagSet(Message.OOB) && added) {
      try {
        up_prot.up(evt);
      } catch (Throwable t) {
        log.error("couldn't deliver OOB message " + msg, t);
      }
    }

    final AtomicBoolean processing = win.getProcessing();
    if (!processing.compareAndSet(false, true)) {
      return;
    }

    // try to remove (from the AckReceiverWindow) as many messages as possible and pass them up

    // Prevents concurrent passing up of messages by different threads
    // (http://jira.jboss.com/jira/browse/JGRP-198);
    // this is all the more important once we have a concurrent stack
    // (http://jira.jboss.com/jira/browse/JGRP-181),
    // where lots of threads can come up to this point concurrently, but only 1 is allowed to pass
    // at a time
    // We *can* deliver messages from *different* senders concurrently, e.g. reception of P1, Q1,
    // P2, Q2 can result in
    // delivery of P1, Q1, Q2, P2: FIFO (implemented by UNICAST) says messages need to be delivered
    // only in the
    // order in which they were sent by their senders
    boolean released_processing = false;
    try {
      while (true) {
        List<Message> msgs =
            win.removeMany(processing, true, max_msg_batch_size); // remove my own messages
        if (msgs == null || msgs.isEmpty()) {
          released_processing = true;
          return;
        }

        for (Message m : msgs) {
          // discard OOB msg: it has already been delivered
          // (http://jira.jboss.com/jira/browse/JGRP-377)
          if (m.isFlagSet(Message.OOB)) continue;
          try {
            up_prot.up(new Event(Event.MSG, m));
          } catch (Throwable t) {
            log.error("couldn't deliver message " + m, t);
          }
        }
      }
    } finally {
      // processing is always set in win.remove(processing) above and never here ! This code is just
      // a
      // 2nd line of defense should there be an exception before win.remove(processing) sets
      // processing
      if (!released_processing) processing.set(false);
    }
  }
コード例 #2
0
ファイル: UNICAST2.java プロジェクト: xiangxuner/JGroups
  /**
   * Check whether the hashmap contains an entry e for <code>sender</code> (create if not). If
   * e.received_msgs is null and <code>first</code> is true: create a new AckReceiverWindow(seqno)
   * and add message. Set e.received_msgs to the new window. Else just add the message.
   */
  protected void handleDataReceived(
      Address sender, long seqno, short conn_id, boolean first, Message msg, Event evt) {
    if (log.isTraceEnabled()) {
      StringBuilder sb = new StringBuilder();
      sb.append(local_addr).append(" <-- DATA(").append(sender).append(": #").append(seqno);
      if (conn_id != 0) sb.append(", conn_id=").append(conn_id);
      if (first) sb.append(", first");
      sb.append(')');
      log.trace(sb);
    }

    ReceiverEntry entry = getReceiverEntry(sender, seqno, first, conn_id);
    if (entry == null) return;
    if (conn_expiry_timeout > 0) entry.update();
    Table<Message> win = entry.received_msgs;
    boolean added = win.add(seqno, msg); // win is guaranteed to be non-null if we get here
    num_msgs_received++;

    if (added) {
      int len = msg.getLength();
      if (len > 0 && entry.incrementStable(len))
        sendStableMessage(
            sender, entry.recv_conn_id, win.getHighestDelivered(), win.getHighestReceived());
    }

    // An OOB message is passed up immediately. Later, when remove() is called, we discard it. This
    // affects ordering !
    // http://jira.jboss.com/jira/browse/JGRP-377
    if (msg.isFlagSet(Message.OOB) && added) {
      try {
        up_prot.up(evt);
      } catch (Throwable t) {
        log.error("couldn't deliver OOB message " + msg, t);
      }
    }

    final AtomicBoolean processing = win.getProcessing();
    if (!processing.compareAndSet(false, true)) {
      return;
    }

    // Try to remove as many messages as possible and pass them up.
    // Prevents concurrent passing up of messages by different threads
    // (http://jira.jboss.com/jira/browse/JGRP-198);
    // this is all the more important once we have a concurrent stack
    // (http://jira.jboss.com/jira/browse/JGRP-181),
    // where lots of threads can come up to this point concurrently, but only 1 is allowed to pass
    // at a time
    // We *can* deliver messages from *different* senders concurrently, e.g. reception of P1, Q1,
    // P2, Q2 can result in
    // delivery of P1, Q1, Q2, P2: FIFO (implemented by UNICAST) says messages need to be delivered
    // only in the
    // order in which they were sent by their senders
    boolean released_processing = false;
    try {
      while (true) {
        List<Message> msgs =
            win.removeMany(processing, true, max_msg_batch_size); // remove my own messages
        if (msgs == null || msgs.isEmpty()) {
          released_processing = true;
          return;
        }

        for (Message m : msgs) {
          // discard OOB msg: it has already been delivered
          // (http://jira.jboss.com/jira/browse/JGRP-377)
          if (m.isFlagSet(Message.OOB)) continue;
          try {
            up_prot.up(new Event(Event.MSG, m));
          } catch (Throwable t) {
            log.error("couldn't deliver message " + m, t);
          }
        }
      }
    } finally {
      // processing is always set in win.remove(processing) above and never here ! This code is just
      // a
      // 2nd line of defense should there be an exception before win.remove(processing) sets
      // processing
      if (!released_processing) processing.set(false);
    }
  }