public int compare(Object a, Object b) {
RemoteFileDesc pongA = (RemoteFileDesc) a;
RemoteFileDesc pongB = (RemoteFileDesc) b;
// Multicasts are best
if (pongA.isReplyToMulticast() != pongB.isReplyToMulticast()) {
if (pongA.isReplyToMulticast()) return -1;
else return 1;
}
// HeadPongs with highest number of free slots get the highest priority
if (pongA.getQueueStatus() > pongB.getQueueStatus()) return 1;
else if (pongA.getQueueStatus() < pongB.getQueueStatus()) return -1;
// Within the same queue rank, firewalled hosts get priority
if (pongA.needsPush() != pongB.needsPush()) {
if (pongA.needsPush()) return -1;
else return 1;
}
// Within the same queue/fwall, partial hosts get priority
if (pongA.isPartialSource() != pongB.isPartialSource()) {
if (pongA.isPartialSource()) return -1;
else return 1;
}
// the two pongs seem completely the same
return pongA.hashCode() - pongB.hashCode();
}
public synchronized RemoteFileDesc getBest() throws NoSuchElementException {
if (!hasMore()) return null;
RemoteFileDesc ret;
// try a verified host
if (!verifiedHosts.isEmpty()) {
LOG.debug("getting a verified host");
ret = (RemoteFileDesc) verifiedHosts.first();
verifiedHosts.remove(ret);
} else {
LOG.debug("getting a non-verified host");
// use the legacy ranking logic to select a non-verified host
Iterator dual = new DualIterator(testedLocations.iterator(), newHosts.iterator());
ret = LegacyRanker.getBest(dual);
newHosts.remove(ret);
testedLocations.remove(ret);
if (ret.needsPush()) {
for (Iterator iter = ret.getPushProxies().iterator(); iter.hasNext(); )
pingedHosts.remove(iter.next());
} else pingedHosts.remove(ret);
}
pingNewHosts();
if (LOG.isDebugEnabled())
LOG.debug("the best host we came up with is " + ret + " " + ret.getPushAddr());
return ret;
}
/** Informs the Ranker that a host has replied with a HeadPing */
public void processMessage(Message m, ReplyHandler handler) {
MeshHandler mesh;
RemoteFileDesc rfd;
Collection alts = null;
// this -> meshHandler NOT ok
synchronized (this) {
if (!running) return;
if (!(m instanceof HeadPong)) return;
HeadPong pong = (HeadPong) m;
if (!pingedHosts.containsKey(handler)) return;
rfd = (RemoteFileDesc) pingedHosts.remove(handler);
testedLocations.remove(rfd);
if (LOG.isDebugEnabled()) {
LOG.debug(
"received a pong "
+ pong
+ " from "
+ handler
+ " for rfd "
+ rfd
+ " with PE "
+ rfd.getPushAddr());
}
// older push proxies do not route but respond directly, we want to get responses
// from other push proxies
if (!pong.hasFile() && !pong.isGGEPPong() && rfd.needsPush()) return;
// if the pong is firewalled, remove the other proxies from the
// pinged set
if (pong.isFirewalled()) {
for (Iterator iter = rfd.getPushProxies().iterator(); iter.hasNext(); )
pingedHosts.remove(iter.next());
}
mesh = meshHandler;
if (pong.hasFile()) {
// update the rfd with information from the pong
pong.updateRFD(rfd);
// if the remote host is busy, re-add him for later ranking
if (rfd.isBusy()) newHosts.add(rfd);
else verifiedHosts.add(rfd);
alts = pong.getAllLocsRFD(rfd);
}
}
// if the pong didn't have the file, drop it
// otherwise add any altlocs the pong had to our known hosts
if (alts == null) mesh.informMesh(rfd, false);
else mesh.addPossibleSources(alts);
}
/** pings a bunch of hosts if necessary */
private void pingNewHosts() {
// if we have reached our desired # of altlocs, don't ping
if (isCancelled()) return;
// if we don't have anybody to ping, don't ping
if (!hasNonBusy()) return;
// if we haven't found a single RFD with URN, don't ping anybody
if (sha1 == null) return;
// if its not time to ping yet, don't ping
// use the same interval as workers for now
long now = System.currentTimeMillis();
if (now - lastPingTime < DownloadSettings.WORKER_INTERVAL.getValue()) return;
// create a ping for the non-firewalled hosts
HeadPing ping = new HeadPing(myGUID, sha1, getPingFlags());
// prepare a batch of hosts to ping
int batch = DownloadSettings.PING_BATCH.getValue();
List toSend = new ArrayList(batch);
int sent = 0;
for (Iterator iter = newHosts.iterator(); iter.hasNext() && sent < batch; ) {
RemoteFileDesc rfd = (RemoteFileDesc) iter.next();
if (rfd.isBusy(now)) continue;
iter.remove();
if (rfd.needsPush()) {
if (rfd.getPushProxies().size() > 0 && rfd.getSHA1Urn() != null) pingProxies(rfd);
} else {
pingedHosts.put(rfd, rfd);
toSend.add(rfd);
}
testedLocations.add(rfd);
sent++;
}
if (LOG.isDebugEnabled()) {
LOG.debug(
"\nverified hosts "
+ verifiedHosts.size()
+ "\npingedHosts "
+ pingedHosts.values().size()
+ "\nnewHosts "
+ newHosts.size()
+ "\npinging hosts: "
+ sent);
}
pinger.rank(toSend, null, this, ping);
lastPingTime = now;
}