/* PeerCheckTasks - TimerTask that checks for good/bad up/downloaders.
Copyright (C) 2003 Mark J. Wielaard
This file is part of Snark.
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, 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.
*/
package org.klomp.snark;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import net.i2p.data.DataHelper;
import net.i2p.util.Log;
import org.klomp.snark.dht.DHT;
/**
* TimerTask that checks for good/bad up/downloader. Works together
* with the PeerCoordinator to select which Peers get (un)choked.
*/
class PeerCheckerTask implements Runnable
{
private static final long KILOPERSECOND = 1024*(PeerCoordinator.CHECK_PERIOD/1000);
private final PeerCoordinator coordinator;
private final I2PSnarkUtil _util;
private final Log _log;
private final Random random;
private int _runCount;
PeerCheckerTask(I2PSnarkUtil util, PeerCoordinator coordinator)
{
_util = util;
_log = util.getContext().logManager().getLog(PeerCheckerTask.class);
random = util.getContext().random();
this.coordinator = coordinator;
}
public void run()
{
_runCount++;
List<Peer> peerList = coordinator.peerList();
if (peerList.isEmpty() || coordinator.halted()) {
coordinator.setRateHistory(0, 0);
return;
}
// Calculate total uploading and worst downloader.
long worstdownload = Long.MAX_VALUE;
Peer worstDownloader = null;
int uploaders = 0;
int interestedUploaders = 0;
int removedCount = 0;
long uploaded = 0;
long downloaded = 0;
// Keep track of peers we remove now,
// we will add them back to the end of the list.
List<Peer> removed = new ArrayList<Peer>();
int uploadLimit = coordinator.allowedUploaders();
boolean overBWLimit = coordinator.overUpBWLimit();
if (_log.shouldLog(Log.DEBUG))
_log.debug("START peers: " + peerList.size() + " uploaders: " + coordinator.getUploaders() +
" interested: " + coordinator.getInterestedUploaders() +
" limit: " + uploadLimit + " overBW? " + overBWLimit);
DHT dht = _util.getDHT();
int i = 0;
for (Peer peer : peerList) {
i++;
// Remove dying peers
if (!peer.isConnected())
{
// This was just a failsafe, right?
//it.remove();
//coordinator.removePeerFromPieces(peer);
//coordinator.peerCount = coordinator.peers.size();
continue;
}
if (peer.getInactiveTime() > PeerCoordinator.MAX_INACTIVE) {
if (_log.shouldLog(Log.WARN))
_log.warn("Disconnecting peer idle " +
DataHelper.formatDuration(peer.getInactiveTime()) + ": " + peer);
peer.disconnect();
continue;
}
// we only count choking AND interested, so as not to steal a slot
// from some other torrent
if (peer.isInterested() && !peer.isChoking())
uploaders++;
long upload = peer.getUploaded();
uploaded += upload;
long download = peer.getDownloaded();
downloaded += download;
peer.setRateHistory(upload, download);
peer.resetCounters();
if (_log.shouldLog(Log.DEBUG)) {
_log.debug(peer + ":"
+ " ul: " + upload*1024/KILOPERSECOND
+ " dl: " + download*1024/KILOPERSECOND
+ " i: " + peer.isInterested()
+ " I: " + peer.isInteresting()
+ " c: " + peer.isChoking()
+ " C: " + peer.isChoked());
}
// Choke a percentage of them rather than all so it isn't so drastic...
// unless this torrent is over the limit all by itself.
// choke 5/8 of the time when seeding and 3/8 when leeching
boolean overBWLimitChoke = upload > 0 &&
((overBWLimit && (random.nextInt(8) > (coordinator.completed() ? 2 : 4))) ||
(coordinator.overUpBWLimit(uploaded)));
// If we are at our max uploaders and we have lots of other
// interested peers try to make some room.
// (Note use of coordinator.uploaders)
int cup = coordinator.getUploaders();
if (((cup == uploadLimit
&& coordinator.getInterestedAndChoking() > 0)
|| cup > uploadLimit
|| overBWLimitChoke)
&& !peer.isChoking())
{
// Check if it still wants pieces from us.
if (!peer.isInterested())
{
// Note that we only choke if we are over our limits,
// so a peer may remain unchoked even if uninterested.
if (_log.shouldLog(Log.DEBUG))
_log.debug("Choke uninterested peer: " + peer);
peer.setChoking(true);
uploaders--;
coordinator.decrementUploaders(false);
// Put it at the back of the list
removed.add(peer);
}
else if (overBWLimitChoke)
{
if (_log.shouldLog(Log.DEBUG))
_log.debug("BW limit (" + upload + "/" + uploaded + "), choke peer: " + peer);
peer.setChoking(true);
uploaders--;
interestedUploaders--;
coordinator.decrementUploaders(true);
removedCount++;
// Put it at the back of the list for fairness, even though we won't be unchoking this time
removed.add(peer);
}
else if (peer.isInteresting() && peer.isChoked())
{
// If they are choking us make someone else a downloader
if (_log.shouldLog(Log.DEBUG))
_log.debug("Choke choking peer: " + peer);
peer.setChoking(true);
uploaders--;
interestedUploaders--;
coordinator.decrementUploaders(true);
removedCount++;
// Put it at the back of the list
removed.add(peer);
}
else if (!peer.isInteresting() && !coordinator.completed())
{
// If they aren't interesting make someone else a downloader
if (_log.shouldLog(Log.DEBUG))
_log.debug("Choke uninteresting peer: " + peer);
peer.setChoking(true);
uploaders--;
interestedUploaders--;
coordinator.decrementUploaders(true);
removedCount++;
// Put it at the back of the list
removed.add(peer);
}
else if (peer.isInteresting()
&& !peer.isChoked()
&& download == 0)
{
// We are downloading but didn't receive anything...
if (_log.shouldLog(Log.DEBUG))
_log.debug("Choke downloader that doesn't deliver: " + peer);
peer.setChoking(true);
uploaders--;
interestedUploaders--;
coordinator.decrementUploaders(true);
removedCount++;
// Put it at the back of the list
removed.add(peer);
}
else if (peer.isInteresting() && !peer.isChoked() &&
download < worstdownload)
{
// Make sure download is good if we are uploading
worstdownload = download;
worstDownloader = peer;
}
else if (upload < worstdownload && coordinator.completed())
{
// Make sure upload is good if we are seeding
worstdownload = upload;
worstDownloader = peer;
}
}
peer.retransmitRequests();
// send PEX, about every 12 minutes
if (((_runCount + i) % 17) == 0 && !peer.isCompleted())
coordinator.sendPeers(peer);
// send Comment Request, about every 30 minutes
if ( /* comments enabled && */ ((_runCount + i) % 47) == 0)
coordinator.sendCommentReq(peer);
// cheap failsafe for seeds connected to seeds, stop pinging and hopefully
// the inactive checker (above) will eventually disconnect it
if (coordinator.getNeededLength() > 0 || !peer.isCompleted())
peer.keepAlive();
// announce them to local tracker (TrackerClient does this too)
if (dht != null && (_runCount % 5) == 0) {
dht.announce(coordinator.getInfoHash(), peer.getPeerID().getDestHash(),
peer.isCompleted());
}
} // for peer
// Resync actual uploaders value
// (can shift a bit by disconnecting peers)
coordinator.setUploaders(uploaders, interestedUploaders);
// Remove the worst downloader if needed. (uploader if seeding)
if (((uploaders == uploadLimit
&& coordinator.getInterestedAndChoking() > 0)
|| uploaders > uploadLimit)
&& worstDownloader != null)
{
if (_log.shouldLog(Log.DEBUG))
_log.debug("Choke worst downloader: " + worstDownloader);
worstDownloader.setChoking(true);
coordinator.decrementUploaders(worstDownloader.isInterested());
removedCount++;
// Put it at the back of the list
removed.add(worstDownloader);
}
boolean coordOver = coordinator.overUpBWLimit(uploaded);
synchronized (coordinator.peers) {
if ((!overBWLimit) && !coordOver) {
// Optimistically unchoke a peer
// must be called inside synch
coordinator.unchokePeer();
}
// Put peers back at the end of the list that we removed earlier.
for(Peer peer : removed) {
if (coordinator.peers.remove(peer))
coordinator.peers.add(peer);
}
}
coordinator.addInterestedAndChoking(removedCount);
// store the rates
coordinator.setRateHistory(uploaded, downloaded);
if (_log.shouldLog(Log.DEBUG))
_log.debug("END peers: " + peerList.size() + " uploaders: " + uploaders +
" interested: " + interestedUploaders);
// close out unused files, but we don't need to do it every time
Storage storage = coordinator.getStorage();
if (storage != null) {
// The more files a torrent has, the more often we call the cleaner,
// to keep from running out of FDs
int files = storage.getFileCount();
int skip;
if (files == 1)
skip = 6;
else if (files <= 4)
skip = 4;
else if (files <= 20)
skip = 3;
else if (files <= 50)
skip = 2;
else
skip = 1;
if ((_runCount % skip) == 0)
storage.cleanRAFs();
}
// announce ourselves to local tracker (TrackerClient does this too)
if (dht != null && (_runCount % 16) == 0) {
dht.announce(coordinator.getInfoHash(), coordinator.completed());
}
}
}