Author: toad
Date: 2006-08-15 18:42:21 +0000 (Tue, 15 Aug 2006)
New Revision: 10094
Modified:
trunk/freenet/src/freenet/io/xfer/BlockTransmitter.java
trunk/freenet/src/freenet/io/xfer/PacketThrottle.java
Log:
Schedule all transfers for a peer collectively.
Throttles start in TCP-like "slow start" mode, which rapidly increases
bandwidth until a packet is lost.
NEEDS TESTING!
Modified: trunk/freenet/src/freenet/io/xfer/BlockTransmitter.java
===================================================================
--- trunk/freenet/src/freenet/io/xfer/BlockTransmitter.java 2006-08-15
18:39:59 UTC (rev 10093)
+++ trunk/freenet/src/freenet/io/xfer/BlockTransmitter.java 2006-08-15
18:42:21 UTC (rev 10094)
@@ -143,11 +143,11 @@
/** @return True if _sendComplete */
private void delay(long startCycleTime) {
- // Get the current inter-packet delay
- long delay = throttle.getDelay();
- Logger.minor(this, "Throttle delay: "+delay);
-
long startThrottle = System.currentTimeMillis();
+
+ // Get the current inter-packet delay
+ long end =
throttle.scheduleDelay(startThrottle);
+
_masterThrottle.blockingGrab(PACKET_SIZE);
long now = System.currentTimeMillis();
@@ -156,8 +156,6 @@
((PeerNode)_destination).reportThrottledPacketSendTime(delayTime);
- long end = startCycleTime + delay;
-
if(now > end) return;
while(now < end) {
now = System.currentTimeMillis();
Modified: trunk/freenet/src/freenet/io/xfer/PacketThrottle.java
===================================================================
--- trunk/freenet/src/freenet/io/xfer/PacketThrottle.java 2006-08-15
18:39:59 UTC (rev 10093)
+++ trunk/freenet/src/freenet/io/xfer/PacketThrottle.java 2006-08-15
18:42:21 UTC (rev 10094)
@@ -26,8 +26,9 @@
public class PacketThrottle {
- protected static final float PACKET_DROP_DECREASE_MULTIPLE = 0.875f;
- protected static final float PACKET_TRANSMIT_INCREMENT = (4 * (1 -
(PACKET_DROP_DECREASE_MULTIPLE * PACKET_DROP_DECREASE_MULTIPLE))) / 3;
+ protected static final double PACKET_DROP_DECREASE_MULTIPLE = 0.875;
+ protected static final double PACKET_TRANSMIT_INCREMENT = (4 * (1 -
(PACKET_DROP_DECREASE_MULTIPLE * PACKET_DROP_DECREASE_MULTIPLE))) / 3;
+ protected static final double SLOW_START_DIVISOR = 3.0;
protected static final long MAX_DELAY = 1000;
protected static final long MIN_DELAY = 25;
public static final String VERSION = "$Id: PacketThrottle.java,v 1.3
2005/08/25 17:28:19 amphibian Exp $";
@@ -37,6 +38,9 @@
private long _roundTripTime = 500, _totalPackets, _droppedPackets;
private float _simulatedWindowSize = 2;
private final int PACKET_SIZE;
+ /** Last return of scheduleDelay(); time before which no packet may be
sent */
+ private long lastScheduledDelay;
+ private boolean slowStart = true;
/**
* Create a PacketThrottle for a given peer.
@@ -67,12 +71,17 @@
_droppedPackets++;
_totalPackets++;
_simulatedWindowSize *= PACKET_DROP_DECREASE_MULTIPLE;
+ slowStart = false;
Logger.minor(this, "notifyOfPacketLost(): "+this);
}
public synchronized void notifyOfPacketAcknowledged() {
_totalPackets++;
- _simulatedWindowSize += (PACKET_TRANSMIT_INCREMENT /
_simulatedWindowSize);
+ if(slowStart) {
+ _simulatedWindowSize += _simulatedWindowSize /
SLOW_START_DIVISOR;
+ } else {
+ _simulatedWindowSize += (PACKET_TRANSMIT_INCREMENT /
_simulatedWindowSize);
+ }
Logger.minor(this, "notifyOfPacketAcked(): "+this);
}
@@ -93,4 +102,16 @@
+ _simulatedWindowSize + ", r:" +
_roundTripTime + ", d:"
+ (((float) _droppedPackets / (float)
_totalPackets)) + ") for "+_peer;
}
+
+ /**
+ * Schedule a delay. This method implements the global congestion
window for a given
+ * peer.
+ * @param now The current time, in millis.
+ * @return The time, in millis, after which a packet may be sent.
+ */
+ public synchronized long scheduleDelay(long now) {
+ if(now > lastScheduledDelay) lastScheduledDelay = now;
+ lastScheduledDelay += getDelay();
+ return lastScheduledDelay;
+ }
}
