/*
* Created on Sep 28, 2004
* Created by Alon Rohter
* Copyright (C) 2004, 2005, 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
package com.aelitis.azureus.core.networkmanager.impl;
import java.io.IOException;
import java.util.*;
import org.gudy.azureus2.core3.util.*;
import com.aelitis.azureus.core.networkmanager.*;
import com.aelitis.azureus.core.peermanager.messaging.*;
/**
* A rate-controlled write entity backed by multiple peer connections, with an
* emphasis on transmitting packets with full payloads, i.e. it writes to the
* transport in mss-sized chunks if at all possible. It also employs fair,
* round-robin write scheduling, where connections each take turns writing a
* single full packet per round.
*/
public class MultiPeerUploader implements RateControlledEntity {
private static final int FLUSH_CHECK_LOOP_TIME = 500; //500ms
private static final int FLUSH_WAIT_TIME = 3*1000; //3sec no-new-data wait before forcing write flush
private long last_flush_check_time = 0;
private final RateHandler rate_handler;
private boolean destroyed = false;
private final HashMap waiting_connections = new HashMap();
private final LinkedList ready_connections = new LinkedList();
private final AEMonitor lists_lock = new AEMonitor( "PacketFillingMultiPeerUploader:lists_lock" );
/**
* Create a new packet-filling multi-peer upload entity,
* rate-controlled by the given handler.
* @param rate_handler listener to handle upload rate limits
*/
public MultiPeerUploader( RateHandler rate_handler ) {
this.rate_handler = rate_handler;
}
/**
* Checks the connections in the waiting list to see if it's time to be force-flushed.
*/
private void flushCheck() {
long diff = SystemTime.getCurrentTime() - last_flush_check_time;
if( !destroyed && (diff > FLUSH_CHECK_LOOP_TIME || diff < 0 ) ) {
try { lists_lock.enter();
long current_time = SystemTime.getCurrentTime();
for( Iterator i = waiting_connections.entrySet().iterator(); i.hasNext(); ) {
Map.Entry entry = (Map.Entry)i.next();
PeerData peer_data = (PeerData)entry.getValue();
long wait_time = current_time - peer_data.last_message_added_time;
if( wait_time > FLUSH_WAIT_TIME || wait_time < 0 ) { //time to force flush
NetworkConnectionBase conn = (NetworkConnectionBase)entry.getKey();
if( conn.getOutgoingMessageQueue().getTotalSize() > 0 ) { //has data to flush
conn.getOutgoingMessageQueue().cancelQueueListener( peer_data.queue_listener ); //cancel the listener
i.remove(); //remove from the waiting list
addToReadyList( conn );
}
else { //no data, so reset flush wait time
peer_data.last_message_added_time = current_time;
}
}
}
}
finally { lists_lock.exit(); }
last_flush_check_time = SystemTime.getCurrentTime();
}
}
/**
* Destroy this upload entity.
* Note: Removes all peer connections in the process.
*/
public void destroy() {
destroyed = true;
try {
lists_lock.enter();
//remove and cancel all connections in waiting list
for( Iterator i = waiting_connections.entrySet().iterator(); i.hasNext(); ) {
Map.Entry entry = (Map.Entry)i.next();
NetworkConnectionBase conn = (NetworkConnectionBase)entry.getKey();
PeerData data = (PeerData)entry.getValue();
conn.getOutgoingMessageQueue().cancelQueueListener( data.queue_listener );
}
waiting_connections.clear();
//remove from ready list
ready_connections.clear();
}
finally {
lists_lock.exit();
}
}
/**
* Add the given connection to be managed by this upload entity.
* @param peer_connection to be write managed
*/
public void addPeerConnection( NetworkConnectionBase peer_connection ) {
int mss_size = peer_connection.getMssSize();
boolean has_urgent_data = peer_connection.getOutgoingMessageQueue().hasUrgentMessage();
int num_bytes_ready = peer_connection.getOutgoingMessageQueue().getTotalSize();
if( num_bytes_ready >= mss_size || has_urgent_data ) { //has a full packet's worth, or has urgent data
addToReadyList( peer_connection );
}
else { //has data to send, but not enough for a full packet
addToWaitingList( peer_connection );
}
}
/**
* Remove the given connection from this upload entity.
* @param peer_connection to be removed
* @return true if the connection was found and removed, false if not removed
*/
public boolean removePeerConnection( NetworkConnectionBase peer_connection ) {
try {
lists_lock.enter();
//look for the connection in the waiting list and cancel listener if found
PeerData peer_data = (PeerData)waiting_connections.remove( peer_connection );
if( peer_data != null ) {
peer_connection.getOutgoingMessageQueue().cancelQueueListener( peer_data.queue_listener );
return true;
}
//look for the connection in the ready list
if( ready_connections.remove( peer_connection ) ) {
return true;
}
return false;
}
finally {
lists_lock.exit();
}
}
//connections with less than a packet's worth of data
private void addToWaitingList( final NetworkConnectionBase conn ) {
final PeerData peer_data = new PeerData();
OutgoingMessageQueue.MessageQueueListener listener = new OutgoingMessageQueue.MessageQueueListener() {
public boolean messageAdded( Message message ) { return true; }
public void messageQueued( Message message ) { //connection now has more data to send
try {
lists_lock.enter();
if( waiting_connections.get( conn ) == null ) { //connection has already been removed from the waiting list
return; //stop further processing
}
int mss_size = conn.getMssSize();
boolean has_urgent_data = conn.getOutgoingMessageQueue().hasUrgentMessage();
int num_bytes_ready = conn.getOutgoingMessageQueue().getTotalSize();
if( num_bytes_ready >= mss_size || has_urgent_data ) { //has a full packet's worth, or has urgent data
waiting_connections.remove( conn ); //remove from waiting list
conn.getOutgoingMessageQueue().cancelQueueListener( this ); //cancel this listener
addToReadyList( conn );
}
else { //still not enough data for a full packet
if ( !peer_data.bumped ){
// only do this once to avoid the possibility that, for example, sending a have
// every 2.9 seconds can result in them being delayed for a significant amount
// of time (e.g. 60 seconds +...)
peer_data.bumped = true;
peer_data.last_message_added_time = SystemTime.getCurrentTime(); //update last message added time
}
}
}
finally {
lists_lock.exit();
}
}
public void messageRemoved( Message message ) {/*ignore*/}
public void messageSent( Message message ) {/*ignore*/}
public void protocolBytesSent( int byte_count ) {/*ignore*/}
public void dataBytesSent( int byte_count ) {/*ignore*/}
};
peer_data.queue_listener = listener; //attach listener
peer_data.last_message_added_time = SystemTime.getCurrentTime(); //start flush wait time
peer_data.bumped = false;
try {
lists_lock.enter();
waiting_connections.put( conn, peer_data ); //add to waiting list
conn.getOutgoingMessageQueue().registerQueueListener( listener ); //listen for added data
}
finally {
lists_lock.exit();
}
}
//connections ready to write
private void addToReadyList( final NetworkConnectionBase conn ) {
try {
lists_lock.enter();
ready_connections.addLast( conn ); //add to ready list
}
finally {
lists_lock.exit();
}
}
private int write( EventWaiter waiter, int num_bytes_to_write ) { //TODO: model this class after the simplicity of MultiPeerDownloader
if( num_bytes_to_write < 1 ) {
Debug.out( "num_bytes_to_write < 1" );
return 0; //not allowed to write
}
HashMap connections_to_notify_of_exception = new HashMap();
ArrayList manual_notifications = new ArrayList();
int num_bytes_remaining = num_bytes_to_write;
try {
lists_lock.enter();
int num_unusable_connections = 0;
while( num_bytes_remaining > 0 && num_unusable_connections < ready_connections.size() ) {
NetworkConnectionBase conn = (NetworkConnectionBase)ready_connections.removeFirst();
if( !conn.getTransportBase().isReadyForWrite( waiter ) ) { //not yet ready for writing
ready_connections.addLast( conn ); //re-add to end as currently unusable
num_unusable_connections++;
continue; //move on to the next connection
}
int total_size = conn.getOutgoingMessageQueue().getTotalSize();
if( total_size < 1 ) { //oops, all messages have been removed
addToWaitingList( conn );
continue; //move on to the next connection
}
int mss_size = conn.getMssSize();
int num_bytes_allowed = num_bytes_remaining > mss_size ? mss_size : num_bytes_remaining; //allow a single full packet at most
int num_bytes_available = total_size > mss_size ? mss_size : total_size; //allow a single full packet at most
if( num_bytes_allowed >= num_bytes_available ) { //we're allowed enough (for either a full packet or to drain any remaining data)
int written = 0;
try {
written = conn.getOutgoingMessageQueue().deliverToTransport( num_bytes_available, true );
if( written > 0 ) {
manual_notifications.add( conn ); //register it for manual listener notification
}
boolean has_urgent_data = conn.getOutgoingMessageQueue().hasUrgentMessage();
int remaining = conn.getOutgoingMessageQueue().getTotalSize();
if( remaining >= mss_size || has_urgent_data ) { //still has a full packet's worth, or has urgent data
ready_connections.addLast( conn ); //re-add to end for further writing
num_unusable_connections = 0; //reset the unusable count so that it has a chance to try this connection again in the loop
}
else { //connection does not have enough for a full packet, so remove and place into waiting list
addToWaitingList( conn );
}
}
catch( Throwable e ) { //write exception, so move to waiting list while it waits for removal
if( AEDiagnostics.TRACE_CONNECTION_DROPS ) {
if( e.getMessage() == null ) {
Debug.out( "null write exception message: ", e );
}
else {
if( e.getMessage().indexOf( "An existing connection was forcibly closed by the remote host" ) == -1 &&
e.getMessage().indexOf( "Connection reset by peer" ) == -1 &&
e.getMessage().indexOf( "Broken pipe" ) == -1 &&
e.getMessage().indexOf( "An established connection was aborted by the software in your host machine" ) == -1 ) {
System.out.println( "MP: write exception [" +conn.getTransportBase().getDescription()+ "]: " +e.getMessage() );
}
}
}
if (! (e instanceof IOException )){
Debug.printStackTrace(e);
}
connections_to_notify_of_exception.put( conn, e ); //do exception notification outside of sync'd block
addToWaitingList( conn );
}
num_bytes_remaining -= written;
}
else { //we're not allowed enough to maximize the packet payload
ready_connections.addLast( conn ); //re-add to end as currently unusable
num_unusable_connections++;
continue; //move on to the next connection
}
}
}
finally {
lists_lock.exit();
}
//manual queue listener notifications
for( int i=0; i < manual_notifications.size(); i++ ) {
NetworkConnectionBase conn = (NetworkConnectionBase)manual_notifications.get( i );
conn.getOutgoingMessageQueue().doListenerNotifications();
}
//exception notifications
for( Iterator i = connections_to_notify_of_exception.entrySet().iterator(); i.hasNext(); ) {
Map.Entry entry = (Map.Entry)i.next();
NetworkConnectionBase conn = (NetworkConnectionBase)entry.getKey();
Throwable exception = (Throwable)entry.getValue();
conn.notifyOfException( exception );
}
int num_bytes_written = num_bytes_to_write - num_bytes_remaining;
if( num_bytes_written > 0 ) {
rate_handler.bytesProcessed( num_bytes_written );
}
return num_bytes_written;
}
/**
* Does this entity have data ready for writing.
* @return true if it has data to send, false if empty
*/
/*
public boolean hasWriteDataAvailable() {
if( ready_connections.isEmpty() ) return false;
return true;
}
*/
private static class PeerData {
private OutgoingMessageQueue.MessageQueueListener queue_listener;
private long last_message_added_time;
private boolean bumped;
}
public long
getBytesReadyToWrite()
{
long total = 0;
try {
lists_lock.enter();
for( Iterator i = waiting_connections.keySet().iterator(); i.hasNext(); ) {
NetworkConnectionBase conn = (NetworkConnectionBase)i.next();
total += conn.getOutgoingMessageQueue().getTotalSize();
}
for( Iterator i = ready_connections.iterator(); i.hasNext(); ) {
NetworkConnectionBase conn = (NetworkConnectionBase)i.next();
total += conn.getOutgoingMessageQueue().getTotalSize();
}
}finally{
lists_lock.exit();
}
return( total );
}
public int
getConnectionCount()
{
return( waiting_connections.size() + ready_connections.size());
}
public int
getReadyConnectionCount(
EventWaiter waiter )
{
int total = 0;
try {
lists_lock.enter();
for( Iterator i = waiting_connections.keySet().iterator(); i.hasNext(); ) {
NetworkConnectionBase conn = (NetworkConnectionBase)i.next();
if ( conn.getTransportBase().isReadyForWrite(waiter)){
total++;
}
}
for( Iterator i = ready_connections.iterator(); i.hasNext(); ) {
NetworkConnectionBase conn = (NetworkConnectionBase)i.next();
if ( conn.getTransportBase().isReadyForWrite(waiter)){
total++;
}
}
}finally{
lists_lock.exit();
}
return( total );
}
//////////////// RateControlledWriteEntity implementation ////////////////////
public boolean canProcess( EventWaiter waiter ) {
flushCheck(); //since this method is called repeatedly from a loop, we can use it to check flushes
if( ready_connections.isEmpty() ) return false; //no data to send
if( rate_handler.getCurrentNumBytesAllowed() < 1/*NetworkManager.getTcpMssSize()*/ ) return false;
return true;
}
public boolean doProcessing( EventWaiter waiter ) {
int num_bytes_allowed = rate_handler.getCurrentNumBytesAllowed();
if( num_bytes_allowed < 1 ) return false;
return write( waiter, num_bytes_allowed ) > 0 ? true : false;
}
public int getPriority() {
return RateControlledEntity.PRIORITY_HIGH;
}
public String
getString()
{
String str = "can_process=" + canProcess(null) + ",bytes_allowed=" + rate_handler.getCurrentNumBytesAllowed() + ", waiting ";
try {
lists_lock.enter();
for( Iterator i = waiting_connections.keySet().iterator(); i.hasNext(); ) {
NetworkConnectionBase conn = (NetworkConnectionBase)i.next();
str += "," + conn.getString();
}
str += ": ready ";
for( Iterator i = ready_connections.iterator(); i.hasNext(); ) {
NetworkConnectionBase conn = (NetworkConnectionBase)i.next();
str += "," + conn.getString();
}
}finally{
lists_lock.exit();
}
return( "MPU: " + str );
}
}
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