/* This code is part of Freenet. It is distributed under the GNU General
* Public License, version 2 (or at your option any later version). See
* http://www.gnu.org/ for further details of the GPL. */
package freenet.node;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static java.util.concurrent.TimeUnit.MINUTES;
import static java.util.concurrent.TimeUnit.NANOSECONDS;
import static java.util.concurrent.TimeUnit.SECONDS;
import java.util.ArrayList;
import freenet.l10n.NodeL10n;
import freenet.support.LogThresholdCallback;
import freenet.support.Logger;
import freenet.support.Logger.LogLevel;
import freenet.support.TimeUtil;
import freenet.support.io.NativeThread;
import freenet.support.math.MersenneTwister;
/**
* @author amphibian
*
* Thread that sends a packet whenever: - A packet needs to be resent immediately -
* Acknowledgments or resend requests need to be sent urgently.
*/
// j16sdiz (22-Dec-2008):
// FIXME this is the only class implements Ticker, everbody is using this as
// a generic task scheduler. Either rename this class, or create another tricker for non-Packet tasks
public class PacketSender implements Runnable {
private static volatile boolean logMINOR;
private static volatile boolean logDEBUG;
static {
Logger.registerLogThresholdCallback(new LogThresholdCallback(){
@Override
public void shouldUpdate(){
logMINOR = Logger.shouldLog(LogLevel.MINOR, this);
logDEBUG = Logger.shouldLog(LogLevel.DEBUG, this);
}
});
}
/** Maximum time we will queue a message for in milliseconds */
static final long MAX_COALESCING_DELAY = MILLISECONDS.toMillis(100);
/** Maximum time we will queue a message for in milliseconds if it is bulk data.
* Note that we will send the data immediately anyway because it will normally be big
* enough to send a full packet. However this impacts the choice of whether to send
* realtime or bulk data, see PeerMessageQueue.addMessages(). */
static final long MAX_COALESCING_DELAY_BULK = SECONDS.toMillis(5);
/** If opennet is enabled, and there are fewer than this many connections,
* we MAY attempt to contact old opennet peers (opennet peers we have
* dropped from the routing table but kept around in case we can't connect). */
static final int MIN_CONNECTIONS_TRY_OLD_OPENNET_PEERS = 5;
/** We send connect attempts to old-opennet-peers no more than once every
* this many milliseconds. */
static final long MIN_OLD_OPENNET_CONNECT_DELAY_NO_CONNS = SECONDS.toMillis(10);
/** We send connect attempts to old-opennet-peers no more than once every
* this many milliseconds. */
static final long MIN_OLD_OPENNET_CONNECT_DELAY = SECONDS.toMillis(60);
final NativeThread myThread;
final Node node;
NodeStats stats;
long lastReportedNoPackets;
long lastReceivedPacketFromAnyNode;
private MersenneTwister localRandom;
PacketSender(Node node) {
this.node = node;
myThread = new NativeThread(this, "PacketSender thread for " + node.getDarknetPortNumber(), NativeThread.MAX_PRIORITY, false);
myThread.setDaemon(true);
localRandom = node.createRandom();
}
void start(NodeStats stats) {
this.stats = stats;
Logger.normal(this, "Starting PacketSender");
System.out.println("Starting PacketSender");
myThread.start();
}
private void schedulePeriodicJob() {
node.ticker.queueTimedJob(new Runnable() {
@Override
public void run() {
try {
long now = System.currentTimeMillis();
if (logMINOR)
Logger.minor(PacketSender.class,
"Starting shedulePeriodicJob() at " + now);
PeerManager pm = node.peers;
pm.maybeLogPeerNodeStatusSummary(now);
pm.maybeUpdateOldestNeverConnectedDarknetPeerAge(now);
stats.maybeUpdatePeerManagerUserAlertStats(now);
stats.maybeUpdateNodeIOStats(now);
pm.maybeUpdatePeerNodeRoutableConnectionStats(now);
if (logMINOR)
Logger.minor(PacketSender.class,
"Finished running shedulePeriodicJob() at "
+ System.currentTimeMillis());
} finally {
node.ticker.queueTimedJob(this, 1000);
}
}
}, 1000);
}
@Override
public void run() {
if(logMINOR) Logger.minor(this, "In PacketSender.run()");
freenet.support.Logger.OSThread.logPID(this);
schedulePeriodicJob();
/*
* Index of the point in the nodes list at which we sent a packet and then
* ran out of bandwidth. We start the loop from here next time.
*/
while(true) {
lastReceivedPacketFromAnyNode = lastReportedNoPackets;
try {
realRun();
} catch(Throwable t) {
Logger.error(this, "Caught in PacketSender: " + t, t);
System.err.println("Caught in PacketSender: " + t);
t.printStackTrace();
}
}
}
/**
* Send loop. Strategy:
* - Each peer can tell us when its data needs to be sent by. This is usually 100ms after it
* is posted. It could vary by message type. Acknowledgements also become valid 100ms after
* being queued.
* - If any peer's data is overdue, send the data from the most overdue peer.
* - If there are peers with more than a packet's worth of data queued, send the data from the
* peer with the oldest data.
* - If there are peers with overdue ack's, send to the peer whose acks are oldest.
*
* It does not attempt to ensure fairness, it attempts to minimise latency. Fairness is best
* dealt with at a higher level e.g. requests, although some transfers are not part of requests,
* e.g. bulk f2f transfers, so we may need to reconsider this eventually...
*/
private void realRun() {
long now = System.currentTimeMillis();
PeerManager pm;
PeerNode[] nodes;
pm = node.peers;
nodes = pm.myPeers();
long nextActionTime = Long.MAX_VALUE;
long oldTempNow = now;
final boolean canSendThrottled;
int MAX_PACKET_SIZE = node.darknetCrypto.socket.getMaxPacketSize();
long count = node.outputThrottle.getCount();
if(count > MAX_PACKET_SIZE)
canSendThrottled = true;
else {
long canSendAt = node.outputThrottle.getNanosPerTick() * (MAX_PACKET_SIZE - count);
canSendAt = MILLISECONDS.convert(canSendAt + MILLISECONDS.toNanos(1) - 1, NANOSECONDS);
if(logMINOR)
Logger.minor(this, "Can send throttled packets in "+canSendAt+"ms");
nextActionTime = Math.min(nextActionTime, now + canSendAt);
canSendThrottled = false;
}
/** The earliest time at which a peer needs to send a packet, which is before
* now. Throttled if canSendThrottled, otherwise not throttled.
* Note: we only use it to sort the full-packed peers by priority, don't rely on it when setting nextActionTime!*/
long lowestUrgentSendTime = Long.MAX_VALUE;
/** The peer(s) which lowestUrgentSendTime is referring to */
ArrayList<PeerNode> urgentSendPeers = null;
/** The earliest time at which a peer needs to send a packet, which is after
* now, where there is a full packet's worth of data to send.
* Throttled if canSendThrottled, otherwise not throttled. */
long lowestFullPacketSendTime = Long.MAX_VALUE;
/** The peer(s) which lowestFullPacketSendTime is referring to */
ArrayList<PeerNode> urgentFullPacketPeers = null;
/** The earliest time at which a peer needs to send an ack, before now. */
long lowestAckTime = Long.MAX_VALUE;
/** The peer(s) which lowestAckTime is referring to */
ArrayList<PeerNode> ackPeers = null;
/** The earliest time at which a peer needs to handshake. */
long lowestHandshakeTime = Long.MAX_VALUE;
/** The peer(s) which lowestHandshakeTime is referring to */
ArrayList<PeerNode> handshakePeers = null;
for(PeerNode pn: nodes) {
now = System.currentTimeMillis();
// Basic peer maintenance.
// For purposes of detecting not having received anything, which indicates a
// serious connectivity problem, we want to look for *any* packets received,
// including auth packets.
lastReceivedPacketFromAnyNode =
Math.max(pn.lastReceivedPacketTime(), lastReceivedPacketFromAnyNode);
pn.maybeOnConnect();
if(pn.shouldDisconnectAndRemoveNow() && !pn.isDisconnecting()) {
// Might as well do it properly.
node.peers.disconnectAndRemove(pn, true, true, false);
}
if(pn.isConnected()) {
boolean shouldThrottle = pn.shouldThrottle();
pn.checkForLostPackets();
// Is the node dead?
// It might be disconnected in terms of FNP but trying to reconnect via JFK's, so we need to use the time when we last got a *data* packet.
if(now - pn.lastReceivedDataPacketTime() > pn.maxTimeBetweenReceivedPackets()) {
Logger.normal(this, "Disconnecting from " + pn + " - haven't received packets recently");
// Hopefully this is a transient network glitch, but stuff will have already started to timeout, so lets dump the pending messages.
pn.disconnected(true, false);
continue;
} else if(now - pn.lastReceivedAckTime() > pn.maxTimeBetweenReceivedAcks() && !pn.isDisconnecting()) {
// FIXME better to disconnect immediately??? Or check canSend()???
Logger.normal(this, "Disconnecting from " + pn + " - haven't received acks recently");
// Do it properly.
// There appears to be connectivity from them to us but not from us to them.
// So it is helpful for them to know that we are disconnecting.
node.peers.disconnect(pn, true, true, false, true, false, SECONDS.toMillis(5));
continue;
} else if(pn.isRoutable() && pn.noLongerRoutable()) {
/*
NOTE: Whereas isRoutable() && noLongerRoutable() are generally mutually exclusive, this
code will only execute because of the scheduled-runnable in start() which executes
updateVersionRoutablity() on all our peers. We don't disconnect the peer, but mark it
as being incompatible.
*/
pn.invalidate(now);
Logger.normal(this, "shouldDisconnectNow has returned true : marking the peer as incompatible: "+pn);
continue;
}
// The peer is connected.
if(canSendThrottled || !shouldThrottle) {
// We can send to this peer.
long sendTime = pn.getNextUrgentTime(now);
if(sendTime != Long.MAX_VALUE) {
if(sendTime <= now) {
// Message is urgent.
if(sendTime < lowestUrgentSendTime) {
lowestUrgentSendTime = sendTime;
if(urgentSendPeers != null)
urgentSendPeers.clear();
else
urgentSendPeers = new ArrayList<PeerNode>();
}
if(sendTime <= lowestUrgentSendTime)
urgentSendPeers.add(pn);
} else if(pn.fullPacketQueued()) {
if(sendTime < lowestFullPacketSendTime) {
lowestFullPacketSendTime = sendTime;
if(urgentFullPacketPeers != null)
urgentFullPacketPeers.clear();
else
urgentFullPacketPeers = new ArrayList<PeerNode>();
}
if(sendTime <= lowestFullPacketSendTime)
urgentFullPacketPeers.add(pn);
}
}
} else if(shouldThrottle && !canSendThrottled) {
long ackTime = pn.timeSendAcks();
if(ackTime != Long.MAX_VALUE) {
if(ackTime <= now) {
if(ackTime < lowestAckTime) {
lowestAckTime = ackTime;
if(ackPeers != null)
ackPeers.clear();
else
ackPeers = new ArrayList<PeerNode>();
}
if(ackTime <= lowestAckTime)
ackPeers.add(pn);
}
}
}
if(canSendThrottled || !shouldThrottle) {
long urgentTime = pn.getNextUrgentTime(now);
// Should spam the logs, unless there is a deadlock
if(urgentTime < Long.MAX_VALUE && logMINOR)
Logger.minor(this, "Next urgent time: " + urgentTime + "(in "+(urgentTime - now)+") for " + pn);
nextActionTime = Math.min(nextActionTime, urgentTime);
} else {
nextActionTime = Math.min(nextActionTime, pn.timeCheckForLostPackets());
}
} else
// Not connected
if(pn.noContactDetails())
pn.startARKFetcher();
long handshakeTime = pn.timeSendHandshake(now);
if(handshakeTime != Long.MAX_VALUE) {
if(handshakeTime < lowestHandshakeTime) {
lowestHandshakeTime = handshakeTime;
if(handshakePeers != null)
handshakePeers.clear();
else
handshakePeers = new ArrayList<PeerNode>();
}
if(handshakeTime <= lowestHandshakeTime)
handshakePeers.add(pn);
}
long tempNow = System.currentTimeMillis();
if((tempNow - oldTempNow) > SECONDS.toMillis(5))
Logger.error(this, "tempNow is more than 5 seconds past oldTempNow (" + (tempNow - oldTempNow) + ") in PacketSender working with " + pn.userToString());
oldTempNow = tempNow;
}
// We may send a packet, send an ack-only packet, or send a handshake.
PeerNode toSendPacket = null;
PeerNode toSendAckOnly = null;
PeerNode toSendHandshake = null;
long t = Long.MAX_VALUE;
if(lowestUrgentSendTime <= now) {
// We need to send a full packet.
toSendPacket = urgentSendPeers.get(localRandom.nextInt(urgentSendPeers.size()));
t = lowestUrgentSendTime;
} else if(lowestFullPacketSendTime < Long.MAX_VALUE) {
toSendPacket = urgentFullPacketPeers.get(localRandom.nextInt(urgentFullPacketPeers.size()));
t = lowestFullPacketSendTime;
} else if(lowestAckTime <= now) {
// We need to send an ack
toSendAckOnly = ackPeers.get(localRandom.nextInt(ackPeers.size()));
t = lowestAckTime;
}
if(lowestHandshakeTime <= now && t > lowestHandshakeTime) {
toSendHandshake = handshakePeers.get(localRandom.nextInt(handshakePeers.size()));
toSendPacket = null;
toSendAckOnly = null;
}
if(toSendPacket != null) {
try {
if(toSendPacket.maybeSendPacket(now, false)) {
// Round-robin over the loop to update nextActionTime appropriately
nextActionTime = now;
}
} catch (BlockedTooLongException e) {
Logger.error(this, "Waited too long: "+TimeUtil.formatTime(e.delta)+" to allocate a packet number to send to "+toSendPacket+" : "+("(new packet format)")+" (version "+toSendPacket.getVersionNumber()+") - DISCONNECTING!");
toSendPacket.forceDisconnect();
}
} else if(toSendAckOnly != null) {
try {
if(toSendAckOnly.maybeSendPacket(now, true)) {
// Round-robin over the loop to update nextActionTime appropriately
nextActionTime = now;
}
} catch (BlockedTooLongException e) {
Logger.error(this, "Waited too long: "+TimeUtil.formatTime(e.delta)+" to allocate a packet number to send to "+toSendAckOnly+" : "+("(new packet format)")+" (version "+toSendAckOnly.getVersionNumber()+") - DISCONNECTING!");
toSendAckOnly.forceDisconnect();
}
}
/* Estimating of nextActionTime logic:
* FullPackets:
* - A full packet available, bandwidth available -->> now
* - A full packet available for non-throttled peer -->> now
* - A full packet available, no bandwidth -->> wait till bandwidth available
* - No packet -->> don't care, will wake up anyway when one arrives, goto Nothing
* UrgentMessages: Only applies when there's enough bandwidth to send a full packet, Includes any urgent acks
* - There's an urgent message, deadline(urgentMessage) > now -->> deadline(urgentMessage)
* - There's an urgent message, deadline(urgentMessage) <= now -->> now
* - There's an urgent message, but there's not enough bandwidth for a full packet -->> wait till bandwidth available
* - There's no urgent message -->> don't care, goto Nothing
* Nothing:
* -->> timeCheckForLostPackets
*/
if(toSendHandshake != null) {
// Send handshake if necessary
long beforeHandshakeTime = System.currentTimeMillis();
toSendHandshake.getOutgoingMangler().sendHandshake(toSendHandshake, false);
long afterHandshakeTime = System.currentTimeMillis();
if((afterHandshakeTime - beforeHandshakeTime) > SECONDS.toMillis(2))
Logger.error(this, "afterHandshakeTime is more than 2 seconds past beforeHandshakeTime (" + (afterHandshakeTime - beforeHandshakeTime) + ") in PacketSender working with " + toSendHandshake.userToString());
}
// All of these take into account whether the data can be sent already.
// So we can include them in nextActionTime.
nextActionTime = Math.min(nextActionTime, lowestUrgentSendTime);
nextActionTime = Math.min(nextActionTime, lowestFullPacketSendTime);
nextActionTime = Math.min(nextActionTime, lowestAckTime);
nextActionTime = Math.min(nextActionTime, lowestHandshakeTime);
// FIXME: If we send something we will have to go around the loop again.
// OPTIMISATION: We could track the second best, and check how many are in the array.
/* Attempt to connect to old-opennet-peers.
* Constantly send handshake packets, in order to get through a NAT.
* Most JFK(1)'s are less than 300 bytes. 25*300/15 = avg 500B/sec bandwidth cost.
* Well worth it to allow us to reconnect more quickly. */
OpennetManager om = node.getOpennet();
if(om != null && node.getUptime() > SECONDS.toMillis(30)) {
OpennetPeerNode[] peers = om.getOldPeers();
for(OpennetPeerNode pn : peers) {
long lastConnected = pn.timeLastConnected(now);
if(lastConnected <= 0)
Logger.error(this, "Last connected is zero or negative for old-opennet-peer "+pn);
// Will be removed by next line.
if(now - lastConnected > OpennetManager.MAX_TIME_ON_OLD_OPENNET_PEERS) {
om.purgeOldOpennetPeer(pn);
if(logMINOR) Logger.minor(this, "Removing old opennet peer (too old): "+pn+" age is "+TimeUtil.formatTime(now - lastConnected));
continue;
}
if(pn.isConnected()) continue; // Race condition??
if(pn.noContactDetails()) {
pn.startARKFetcher();
continue;
}
if(pn.shouldSendHandshake()) {
// Send handshake if necessary
long beforeHandshakeTime = System.currentTimeMillis();
pn.getOutgoingMangler().sendHandshake(pn, true);
long afterHandshakeTime = System.currentTimeMillis();
if((afterHandshakeTime - beforeHandshakeTime) > SECONDS.toMillis(2))
Logger.error(this, "afterHandshakeTime is more than 2 seconds past beforeHandshakeTime (" + (afterHandshakeTime - beforeHandshakeTime) + ") in PacketSender working with " + pn.userToString());
}
}
}
long oldNow = now;
// Send may have taken some time
now = System.currentTimeMillis();
if((now - oldNow) > SECONDS.toMillis(10))
Logger.error(this, "now is more than 10 seconds past oldNow (" + (now - oldNow) + ") in PacketSender");
long sleepTime = nextActionTime - now;
// MAX_COALESCING_DELAYms maximum sleep time - same as the maximum coalescing delay
sleepTime = Math.min(sleepTime, MAX_COALESCING_DELAY);
if(now - node.startupTime > MINUTES.toMillis(5))
if(now - lastReceivedPacketFromAnyNode > Node.ALARM_TIME) {
Logger.error(this, "Have not received any packets from any node in last " + SECONDS.convert(Node.ALARM_TIME, MILLISECONDS) + " seconds");
lastReportedNoPackets = now;
}
if(sleepTime > 0) {
// Update logging only when have time to do so
try {
if(logMINOR)
Logger.minor(this, "Sleeping for " + sleepTime);
synchronized(this) {
wait(sleepTime);
}
} catch(InterruptedException e) {
// Ignore, just wake up. Probably we got interrupt()ed
// because a new packet came in.
}
} else {
if(logDEBUG)
Logger.debug(this, "Next urgent time is "+(now - nextActionTime)+"ms in the past");
}
}
/** Wake up, and send any queued packets. */
void wakeUp() {
// Wake up if needed
synchronized(this) {
notifyAll();
}
}
protected String l10n(String key, String[] patterns, String[] values) {
return NodeL10n.getBase().getString("PacketSender."+key, patterns, values);
}
protected String l10n(String key, String pattern, String value) {
return NodeL10n.getBase().getString("PacketSender."+key, pattern, value);
}
}