protected void sendStableMessage(Address dest, short conn_id, long low, long high) {
Message stable_msg = new Message(dest, null, null);
Unicast2Header hdr = Unicast2Header.createStableHeader(conn_id, low, high);
stable_msg.putHeader(this.id, hdr);
stable_msg.setFlag(Message.OOB);
if (log.isTraceEnabled()) {
StringBuilder sb = new StringBuilder();
sb.append(local_addr)
.append(" --> STABLE(")
.append(dest)
.append(": ")
.append(low)
.append("-")
.append(high)
.append(", conn_id=")
.append(conn_id)
.append(")");
log.trace(sb.toString());
}
down_prot.down(new Event(Event.MSG, stable_msg));
ReceiverEntry entry = recv_table.get(dest);
NakReceiverWindow win = entry != null ? entry.received_msgs : null;
if (win != null) win.stable(win.getHighestDelivered());
}
private ReceiverEntry getOrCreateReceiverEntry(Address sender, long seqno, short conn_id) {
NakReceiverWindow win =
new NakReceiverWindow(
sender,
this,
seqno - 1,
timer,
use_range_based_retransmitter,
xmit_table_num_rows,
xmit_table_msgs_per_row,
xmit_table_resize_factor,
xmit_table_max_compaction_time,
xmit_table_automatic_purging);
if (exponential_backoff > 0)
win.setRetransmitTimeouts(new ExponentialInterval(exponential_backoff));
else win.setRetransmitTimeouts(new StaticInterval(timeout));
ReceiverEntry entry = new ReceiverEntry(win, conn_id, max_stable_msgs);
ReceiverEntry entry2 = recv_table.putIfAbsent(sender, entry);
if (entry2 != null) return entry2;
if (log.isTraceEnabled())
log.trace(
local_addr
+ ": created receiver window for "
+ sender
+ " at seqno=#"
+ seqno
+ " for conn-id="
+ conn_id);
return entry;
}
@ManagedOperation(
description =
"Sends a STABLE message to all senders. This causes message purging and potential"
+ " retransmissions from senders")
public void sendStableMessages() {
for (Map.Entry<Address, ReceiverEntry> entry : recv_table.entrySet()) {
Address dest = entry.getKey();
ReceiverEntry val = entry.getValue();
NakReceiverWindow win = val != null ? val.received_msgs : null;
if (win != null) {
long[] tmp = win.getDigest();
long low = tmp[0], high = tmp[1];
if (val.last_highest == high) {
if (val.num_stable_msgs >= val.max_stable_msgs) {
continue;
} else val.num_stable_msgs++;
} else {
val.last_highest = high;
val.num_stable_msgs = 1;
}
sendStableMessage(dest, val.recv_conn_id, low, high);
}
}
}
@ManagedOperation(description = "Compacts the retransmission tables")
public void compact() {
for (Map.Entry<Address, ReceiverEntry> entry : recv_table.entrySet()) {
NakReceiverWindow win = entry.getValue().received_msgs;
win.compact();
}
}
@ManagedOperation(
description = "Purges highes delivered messages and compacts the retransmission tables")
public void purgeAndCompact() {
for (Map.Entry<Address, ReceiverEntry> entry : recv_table.entrySet()) {
NakReceiverWindow win = entry.getValue().received_msgs;
win.stable(win.getHighestDelivered());
win.compact();
}
}
public void removeReceiveConnection(Address mbr) {
ReceiverEntry entry2 = recv_table.remove(mbr);
if (entry2 != null) {
NakReceiverWindow win = entry2.received_msgs;
if (win != null)
sendStableMessage(
mbr, entry2.recv_conn_id, win.getHighestDelivered(), win.getHighestReceived());
entry2.reset();
}
}
@ManagedOperation(description = "Returns the sizes of all NakReceiverWindow.RetransmitTables")
public String printRetransmitTableSizes() {
StringBuilder sb = new StringBuilder();
for (Map.Entry<Address, ReceiverEntry> entry : recv_table.entrySet()) {
NakReceiverWindow win = entry.getValue().received_msgs;
sb.append(entry.getKey() + ": ")
.append(win.getRetransmitTableSize())
.append(" (capacity=" + win.getRetransmitTableCapacity())
.append(", fill factor=" + win.getRetransmitTableFillFactor() + "%)\n");
}
return sb.toString();
}
/**
* 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);
}
}
void reset() {
if (received_msgs != null) received_msgs.destroy();
received_bytes = 0;
last_highest = -1;
num_stable_msgs = 0;
}
