1) Added a UdpSensorList class.

2) Replaced gettimeofday calls with TSC register reads.
3) Removed all recvfrom calls - no overhead for those calls & copying
packets to user space - this does not adversely affect performance.
4) More graphs!! and streamlined error/warning messages to be put into a single
log file.

pelab/magent/UDP/DESIGN_RFC.txt

@@ -163,6 +163,24 @@ We currently ignore the reordering of packets/ACKs on forward/reverse paths.
 If this happens persistently and is perceived as a characteristic of some links,
 then it might need to be addressed.
 
+Optimizations:
+--------------
+
+1) The UdpClient application sends packets at a fixed rate specified at the
+command line. In order to keep of the time, gettimeofday() can be used. But,
+on planet lab using gettimeofday() may cause the program to be scheduled
+out because it is a system call. Instead, the sending times are now
+being calculated by reading the values of the TSC register. Now,
+the deviation between when we wish to send a packet and we actually send
+it is around 2 ms against the 10+ ms when using gettimeofday.
+
+2) Since we capture and process all UDP packets using libpcap, there is no
+need to make recvfrom() calls, either at the sender or at the receiver. Those
+calls have now been removed and we will not incur the overhead of the system calls
+and the time to copy the packets to user space. I ran the application in a controlled
+emulab environment and did not observe any increase in CPU usage when all the received
+UDP packets were being dropped by the kernel ( due to full socket receive buffer ).
+
 
 
 

pelab/magent/UDP/UdpClientDir/Makefile.Client

@@ -10,7 +10,8 @@ OBJECTS=${COMPILE_DIR}/UdpClient.o \
 	${COMPILE_DIR}/UdpMaxDelaySensor.o \
 	${COMPILE_DIR}/UdpThroughputSensor.o \
 	${COMPILE_DIR}/UdpPacketInfo.o \
-	${COMPILE_DIR}/UdpSensor.o
+	${COMPILE_DIR}/UdpSensor.o \
+	${COMPILE_DIR}/UdpSensorList.o
 
 
 COMMON_INCLUDES=UdpLibs.h \
@@ -40,6 +41,9 @@ ${COMPILE_DIR}/UdpPacketInfo.o: UdpPacketInfo.cc UdpPacketInfo.h  ${COMMON_INCLU
 ${COMPILE_DIR}/UdpSensor.o: UdpSensor.cc UdpSensor.h ${COMMON_INCLUDES}
 	${CC} -c ${CFLAGS} -o $@ $<
 
+${COMPILE_DIR}/UdpSensorList.o: UdpSensorList.cc UdpSensorList.h ${COMMON_INCLUDES}
+	${CC} -c ${CFLAGS} -o $@ $<
+
 clean:
 	rm -f ${COMPILE_DIR}/*.o ${EXECUTABLE}
 

pelab/magent/UDP/UdpClientDir/UdpClient.cc

@@ -29,6 +29,7 @@
 #include "UdpMaxDelaySensor.h"
 #include "UdpPacketSensor.h"
 #include "UdpState.h"
+#include "UdpSensorList.h"
 
 pcap_t *pcapDescriptor = NULL;
 UdpThroughputSensor *throughputSensor;
@@ -39,6 +40,19 @@ char localIP[16] = "";
 
 struct UdpState globalUdpState;
 
+struct pcap_stat pcapStats;
+int currentPcapLoss = 0;
+// Use this file handle to log messages - statistics and any warnings/errors.
+std::ofstream logStream;
+UdpSensorList *sensorList;
+
+/* Grab the TSC register. */
+inline volatile unsigned long long RDTSC() {
+   register unsigned long long TSC asm("eax");
+   asm volatile (".byte 0xf, 0x31" : : : "eax", "edx");
+   return TSC;
+}
+
 unsigned long long getTimeMicro()
 {
         struct timeval tp;
@@ -50,11 +64,19 @@ unsigned long long getTimeMicro()
         return (tmpSecVal*1000*1000 + tmpUsecVal);
 }
 
-void handleUDP(struct pcap_pkthdr const *pcap_info, struct udphdr const *udpHdr, u_char *const udpPacketStart, struct ip const *ipPacket)
+void handleUDP(struct pcap_pkthdr const *pcap_info, struct udphdr const *udpHdr, unsigned char *udpPacketStart, struct ip const *ipPacket)
 {
+	// Report any packets dropped in libpcap.
+	pcap_stats(pcapDescriptor, &pcapStats);
+
+	if(pcapStats.ps_drop > currentPcapLoss)
+	{
+		currentPcapLoss += pcapStats.ps_drop;
+		logStream <<"STAT::Number of packets lost in libpcap = "<<currentPcapLoss<<endl;
+	}
 
 	// Get a pointer to the data section of the UDP packet.
-	u_char *dataPtr = udpPacketStart + 8;
+	unsigned char *dataPtr = udpPacketStart + 8;
 	unsigned short udpLen = ntohs(udpHdr->len) - 8;
 
 	//printf("Data being received = %c, %u, %lld, %u\n", *(unsigned char *)(dataPtr), *(unsigned int *)(dataPtr + 1), *(unsigned long long*)(dataPtr + 5), udpLen);
@@ -84,7 +106,7 @@ void handleUDP(struct pcap_pkthdr const *pcap_info, struct udphdr const *udpHdr,
         {
 		if(strcmp( inet_ntoa(ipPacket->ip_dst),localIP ) != 0 )
 		{
-		    packetSensor->capturePacket(reinterpret_cast<char *>(dataPtr), udpLen, overheadLen, timeStamp);
+			sensorList->capturePacket(reinterpret_cast<char *> (dataPtr), udpLen, overheadLen, timeStamp);
 		}
 	}
 	else if(packetType == '1')
@@ -101,27 +123,24 @@ void handleUDP(struct pcap_pkthdr const *pcap_info, struct udphdr const *udpHdr,
 		if(strcmp( inet_ntoa(ipPacket->ip_dst),localIP ) == 0 )
 		{
 			// Pass the captured packet to the udp sensors.
-			packetSensor->capturePacket(reinterpret_cast<char *> (dataPtr), udpLen, overheadLen, timeStamp);
-			minDelaySensor->capturePacket(reinterpret_cast<char *>(dataPtr), udpLen, overheadLen, timeStamp);
-			maxDelaySensor->capturePacket(reinterpret_cast<char *>(dataPtr), udpLen, overheadLen, timeStamp);
-			throughputSensor->capturePacket(reinterpret_cast<char *>(dataPtr), udpLen, overheadLen, timeStamp);
+			sensorList->capturePacket(reinterpret_cast<char *> (dataPtr), udpLen, overheadLen, timeStamp);
 		}
 	}
 	else
 	{
-		printf("ERROR: Unknown UDP packet received from remote agent\n");
+		logStream <<"ERROR::Unknown format UDP packet received from remote agent"<<endl;
 		return;
 	}
 }
 
-int getLinkLayer(struct pcap_pkthdr const *pcap_info, const u_char *pkt_data)
+int getLinkLayer(struct pcap_pkthdr const *pcap_info, unsigned char const *pkt_data)
 {
 	unsigned int caplen = pcap_info->caplen;
 
 	if (caplen < sizeof(struct ether_header))
 	{
-		printf("A captured packet was too short to contain "
-		"an ethernet header");
+		logStream<<"ERROR::A captured packet was too short to contain "
+		"an ethernet header"<<endl;
 		return -1;
 	}
 	else
@@ -131,13 +150,13 @@ int getLinkLayer(struct pcap_pkthdr const *pcap_info, const u_char *pkt_data)
 	}
 }
 
-void pcapCallback(u_char *user, const struct pcap_pkthdr *pcap_info, const u_char *pkt_data)
+void pcapCallback(unsigned char *user, struct pcap_pkthdr const *pcap_info, unsigned char const *pkt_data)
 {
 	int packetType = getLinkLayer(pcap_info, pkt_data);
 
 	if(packetType != ETHERTYPE_IP)
 	{
-		printf("Unknown link layer type: %d\n", packetType);
+		logStream<<"ERROR::Unknown link layer type: "<<packetType<<endl;
 		return;
 	}
 
@@ -146,7 +165,7 @@ void pcapCallback(u_char *user, const struct pcap_pkthdr *pcap_info, const u_cha
 
 	if(bytesLeft < sizeof(struct ip))
 	{
-		printf("Captured packet was too short to contain an IP header.\n");
+		logStream<<"ERROR::Captured packet was too short to contain an IP header"<<endl;
 		return;
 	}
 
@@ -157,19 +176,19 @@ void pcapCallback(u_char *user, const struct pcap_pkthdr *pcap_info, const u_cha
 
 	if(ipVersion != 4)
 	{
-		printf("Captured IP packet is not IPV4.\n");
+		logStream<<"ERROR::Captured IP packet is not IPV4."<<endl;
 		return;
 	}
 
 	if(ipHeaderLength < 5)
 	{
-		printf("Captured IP packet has header less than the minimum 20 bytes.\n");
+		logStream<<"ERROR::Captured IP packet has header less than the minimum 20 bytes.\n"<<endl;
 		return;
 	}
 
 	if(ipPacket->ip_p != IPPROTO_UDP)
 	{
-		printf("Captured packet is not a UDP packet.\n");
+		logStream<<"ERROR::Captured packet is not a UDP packet.\n"<<endl;
 		return;
 	}
 
@@ -185,14 +204,14 @@ void pcapCallback(u_char *user, const struct pcap_pkthdr *pcap_info, const u_cha
 
 	if(bytesLeft < sizeof(struct udphdr))
 	{
-		printf("Captured packet is too small to contain a UDP header.\n");
+		logStream<<"ERROR::Captured packet is too small to contain a UDP header."<<endl;
 		return;
 	}
 
 	handleUDP(pcap_info,udpPacket,udpPacketStart, ipPacket);
 }
 
-void init_pcap(char *interface, unsigned int portNumber)
+int init_pcap(char *interface, unsigned int portNumber)
 {
 	struct bpf_program bpfProg;
 	char errBuf[PCAP_ERRBUF_SIZE];
@@ -209,7 +228,7 @@ void init_pcap(char *interface, unsigned int portNumber)
 
 	if(pcapDescriptor == NULL)
 	{
-		printf("Error opening device %s with libpcap = %s\n", interface, errBuf);
+		logStream<<"ERROR::Error opening device "<<interface<<"  with libpcap = "<< errBuf<<endl;
 		exit(1);
 	}
 
@@ -218,6 +237,8 @@ void init_pcap(char *interface, unsigned int portNumber)
 
 	pcap_setnonblock(pcapDescriptor, 1, errBuf);
 
+	return pcap_get_selectable_fd(pcapDescriptor);
+
 }
 
 int main(int argc, char *argv[]) 
@@ -233,11 +254,12 @@ int main(int argc, char *argv[])
 
 
 	/* check command line args */
-	if(argc < 7) 
+	if(argc < 8) 
 	{
-		printf("usage : %s <local-interface> <local-IP> <serverName> <packetCount> <packetSize> <SendRate-bps>\n", argv[0]);
+		printf("usage : %s <local-interface> <local-IP> <serverName> <packetCount> <packetSize> <SendRate-bps> <CPU-MHZ Integer>\n", argv[0]);
 		exit(1);
 	}
+	logStream.open("stats.log", std::ios::out);
 	strcpy(localIP, argv[2]);
 
 	/* get server IP address (no check if input is IP address or DNS name */
@@ -245,7 +267,7 @@ int main(int argc, char *argv[])
 
 	if(h==NULL) 
 	{
-		printf("%s: unknown host '%s' \n", argv[0], argv[3]);
+		logStream<<"ERROR:: "<<argv[0]<<": unknown host"<< argv[3]<<endl;
 		exit(1);
 	}
 
@@ -262,7 +284,7 @@ int main(int argc, char *argv[])
 
 	if(sd<0) 
 	{
-		printf("%s: cannot open socket \n",argv[0]);
+		logStream<<"ERROR:: "<<argv[0]<<": cannot open socket."<<endl;
 		exit(1);
 	}
 
@@ -274,7 +296,7 @@ int main(int argc, char *argv[])
 	// Set the socket descriptor to be non-blocking.
 	if( fcntl(sd, F_SETFL, flags) < 0)
 	{
-		printf("Error setting non blocking socket flags with fcntl.\n");
+		logStream<<"ERROR::Error setting non blocking socket flags with fcntl."<<endl;
 		exit(1);
 	}
 
@@ -287,25 +309,23 @@ int main(int argc, char *argv[])
 
 	if(rc<0) 
 	{
-		printf("%s: cannot bind port\n", argv[0]);
+		logStream<<"ERROR::"<<argv[0]<<": cannot bind port 3200"<<endl;
 		exit(1);
 	}
 
 	flags = 0;
 
-	// Initialize the libpcap filter.
-	init_pcap(argv[1], htons(cliAddr.sin_port));
-
-	// Open a file and pass the handle to the throughput sensor.
-	std::ofstream logStream;
 
-	logStream.open("stats.log", std::ios::out);
 
 	// Initialize the sensors.
-	packetSensor = new UdpPacketSensor(globalUdpState);
-	throughputSensor = new UdpThroughputSensor(globalUdpState, logStream);
-	maxDelaySensor = new UdpMaxDelaySensor(globalUdpState, logStream);
-	minDelaySensor = new UdpMinDelaySensor(globalUdpState, logStream);
+	sensorList = new UdpSensorList(logStream);
+	sensorList->addSensor(UDP_PACKET_SENSOR);
+	sensorList->addSensor(UDP_THROUGHPUT_SENSOR);
+	sensorList->addSensor(UDP_MINDELAY_SENSOR);
+	sensorList->addSensor(UDP_MAXDELAY_SENSOR);
+
+	// Initialize the libpcap filter.
+	int pcapFD = init_pcap(argv[1], htons(cliAddr.sin_port));
 
 	char packetData[1600];
 	unsigned short int curSeqNum = 0;
@@ -330,25 +350,37 @@ int main(int argc, char *argv[])
 
 	int overheadLen = 20 + 8 + 14 + 4;
 
+	// Fill in the MHz of the CPU - should be read from /proc/cpuinfo
+	long freqDivisor = atoi(argv[7]);
+	//long freqDivisor = 601;
+
 	long long timeInterval = 800000000  / sendRate;
 	timeInterval *= (packetLen + overheadLen);
 	timeInterval /= 100;
 
-	lastSendTime = getTimeMicro();
+	//lastSendTime = getTimeMicro();
+	lastSendTime = RDTSC();
 	echoLen = sizeof(echoServAddr);
 
-	FILE *sendDevFile = fopen("SendDeviation.log", "w");
-
 	/* send data */
 	while(true) 
 	{
 		if(curSeqNum < packetCount)
 		{
-			// UDP sends do not block - we don't need to 
+			// UDP sendTo blocks in Linux - we need to 
 			// check if the socket is ready for writing.
 			FD_SET(sd, &writeFdSet);
 
-			select(sd + 1,NULL,&writeFdSet, NULL,&selectTimeout);
+			// Check whether any data is available in the pcap buffer
+			// for reading.
+			FD_SET(pcapFD, &readFdSet);
+
+			select(sd + pcapFD + 1,&readFdSet,&writeFdSet, NULL,&selectTimeout);
+
+			if(FD_ISSET(pcapFD, &readFdSet) != 0)
+			{
+				  pcap_dispatch(pcapDescriptor, 1, pcapCallback, NULL);
+			}
 
 			if(FD_ISSET(sd, &writeFdSet) != 0)
 			{
@@ -360,10 +392,16 @@ int main(int argc, char *argv[])
 				// For now, take a command line argument giving the rate
 				// at which UDP packets should be sent ( this rate includes
 				// the overhead for UDP, IP & ethernet headers ( &ethernet checksum)
-				curTime = getTimeMicro();
-				if(curTime - lastSendTime > timeInterval)
+
+			//	curTime = getTimeMicro();
+			//	if( (curTime - lastSendTime) > timeInterval)
+
+				curTime = RDTSC();
+				if( (curTime - lastSendTime) > timeInterval*freqDivisor)
 				{
-					logStream << "SendDeviation:TIME="<<curTime<<",Deviation="<< curTime - lastSendTime - timeInterval<<std::endl;
+					logStream << "SendDeviation:TIME="<<curTime<<",Deviation="<< (curTime - lastSendTime)/freqDivisor - timeInterval<<std::endl;
+
+//					logStream << "SendDeviation:TIME="<<curTime<<",Deviation="<< (curTime - lastSendTime) - timeInterval<<std::endl;
 
 					curSeqNum++;
 					// Indicate that this is a data UDP packet - not an ACK.
@@ -396,34 +434,18 @@ int main(int argc, char *argv[])
 
 					if(rc < 0)
 					{
-					    printf("WARNING:Blocked in send = %d\n",errno);
-					}
-					else
-					{
-					  pcap_dispatch(pcapDescriptor, 1, pcapCallback, NULL);
+					    logStream<<"WARNING::Blocked in send, errno = "<<errno<<endl;
 					}
 				}
+				else
+				{
+					usleep(timeInterval - ( curTime - lastSendTime)/freqDivisor );
+		//			usleep(timeInterval - ( curTime - lastSendTime));
+				}
 			}
 
 		}
 
-		// Check whether any data is available in the receive buffer
-		// for reading.
-		FD_SET(sd, &readFdSet);
-
-		select(sd + 1, &readFdSet, NULL, NULL,&selectTimeout);
-
-		if(FD_ISSET(sd, &readFdSet) != 0)
-		{
-			n = recvfrom(sd, msg, MAX_MSG, 0,
-			(struct sockaddr *) &echoServAddr, &echoLen);
-
-			if(n > 0)
-				pcap_dispatch(pcapDescriptor, 1, pcapCallback, NULL);
-		}
-
-
 	}
-	fclose(sendDevFile);
 	return 0;
 }

pelab/magent/UDP/UdpClientDir/UdpLibs.h

@@ -20,7 +20,9 @@ namespace globalConsts {
 
 	const static int redunAckSize = 2*USHORT_INT_SIZE + ULONG_LONG_SIZE;
 	const static int seqNumSize = USHORT_INT_SIZE;
-	const static int minAckPacketSize = 1 + 2*USHORT_INT_SIZE + ULONG_LONG_SIZE;
+	const static int minAckPacketSize = 1 + 2*USHORT_INT_SIZE + 2*ULONG_LONG_SIZE;
 }
 
+enum {UDP_PACKET_SENSOR, UDP_THROUGHPUT_SENSOR, UDP_MINDELAY_SENSOR, UDP_MAXDELAY_SENSOR};
+
 #endif

pelab/magent/UDP/UdpClientDir/UdpMaxDelaySensor.cc

 #include "UdpMaxDelaySensor.h"
 
-UdpMaxDelaySensor::UdpMaxDelaySensor(UdpState &udpStateVal, ofstream &outStreamVal)
+UdpMaxDelaySensor::UdpMaxDelaySensor(UdpState &udpStateVal, ofstream &logStreamVal)
 	: maxDelay(0),
 	udpStateInfo(udpStateVal),
-	outStream(outStreamVal)
+	logStream(logStreamVal)
+{
+
+}
+
+UdpMaxDelaySensor::~UdpMaxDelaySensor()
 {
 
 }
@@ -18,7 +23,7 @@ void UdpMaxDelaySensor::localAck(char *packetData, int Len,int overheadLen, unsi
 {
         if(Len < globalConsts::minAckPacketSize)
         {
-                cout << "Error: UDP packet data sent to MaxDelaySensor::localAck was less than the "
+                logStream << "ERROR::UDP packet data sent to MaxDelaySensor::localAck was less than the "
                         " required minimum "<< globalConsts::minAckPacketSize << " bytes\n";
                 return;
         }
@@ -30,7 +35,7 @@ void UdpMaxDelaySensor::localAck(char *packetData, int Len,int overheadLen, unsi
 
         unsigned short int seqNum = *(unsigned short int *)(packetData + 1);
         unsigned short int echoedPacketSize = *(unsigned short int *)(packetData + 1 + globalConsts::USHORT_INT_SIZE);
-	unsigned long long echoedTimestamp = *(unsigned long long *)(packetData + 1 + 2*globalConsts::USHORT_INT_SIZE);
+	unsigned long long echoedTimestamp = *(unsigned long long *)(packetData + 1 + 2*globalConsts::USHORT_INT_SIZE + globalConsts::ULONG_LONG_SIZE);
         unsigned long long oneWayQueueDelay;
         bool eventFlag = false;
 
@@ -73,9 +78,10 @@ void UdpMaxDelaySensor::localAck(char *packetData, int Len,int overheadLen, unsi
         if(eventFlag == true)
         {
 		// Report the maximum delay
-		cout << "New Max Delay = " << maxDelay << "\n";
+		logStream << "VALUE::New Max Delay = " << maxDelay << "\n";
         }
-	outStream << "MAXD:TIME="<<timeStamp<<",MAXD="<<maxDelay<<endl;
+	logStream << "MAXD:TIME="<<timeStamp<<",MAXD="<<maxDelay<<endl;
+	logStream << "ACTUAL_MAXD:TIME="<<timeStamp<<",ACTUAL_MAXD="<<oneWayQueueDelay<<endl;
 
 	udpStateInfo.maxDelay = maxDelay;
 }

pelab/magent/UDP/UdpClientDir/UdpMaxDelaySensor.h

@@ -10,14 +10,17 @@ class UdpSensor;
 class UdpMaxDelaySensor:public UdpSensor{
 	public:
 
-		explicit UdpMaxDelaySensor(UdpState &udpStateVal, ofstream &outStreamVal);
+		explicit UdpMaxDelaySensor(UdpState &udpStateVal, ofstream &logStreamVal);
+		~UdpMaxDelaySensor();
+
+
 		void localSend(char *packetData, int Len,int overheadLen, unsigned long long timeStamp);
 		void localAck(char *packetData, int Len,int overheadLen, unsigned long long timeStamp);
 
 	private:
 		unsigned long long maxDelay;
 		UdpState &udpStateInfo;
-		ofstream &outStream;
+		ofstream &logStream;
 };
 
 #endif

pelab/magent/UDP/UdpClientDir/UdpMinDelaySensor.cc

 #include "UdpMinDelaySensor.h"
 
-UdpMinDelaySensor::UdpMinDelaySensor(UdpState &udpStateVal, ofstream &outStreamVal)
+UdpMinDelaySensor::UdpMinDelaySensor(UdpState &udpStateVal, ofstream &logStreamVal)
 	: minDelay(ULONG_LONG_MAX),
 	udpStateInfo(udpStateVal),
-	outStream(outStreamVal)
+	logStream(logStreamVal)
+{
+
+}
+
+UdpMinDelaySensor::~UdpMinDelaySensor()
 {
 
 }
@@ -19,7 +24,7 @@ void UdpMinDelaySensor::localAck(char *packetData, int Len,int overheadLen, unsi
 {
         if(Len < globalConsts::minAckPacketSize)
         {
-                cout << "Error: UDP packet data sent to MinDelaySensor::localAck was less than the "
+                logStream << "ERROR::UDP packet data sent to MinDelaySensor::localAck was less than the "
                         " required minimum "<< globalConsts::minAckPacketSize << " bytes\n";
                 return;
         }
@@ -31,7 +36,7 @@ void UdpMinDelaySensor::localAck(char *packetData, int Len,int overheadLen, unsi
 
 	unsigned short int seqNum = *(unsigned short int *)(packetData + 1);
 	unsigned short int echoedPacketSize = *(unsigned short int *)(packetData + 1 + globalConsts::USHORT_INT_SIZE);
-	unsigned long long echoedTimestamp = *(unsigned long long *)(packetData + 1 + 2*globalConsts::USHORT_INT_SIZE);
+	unsigned long long echoedTimestamp = *(unsigned long long *)(packetData + 1 + 2*globalConsts::USHORT_INT_SIZE + globalConsts::ULONG_LONG_SIZE);
 
 	unsigned long long oneWayDelay;
 	bool eventFlag = false;
@@ -73,8 +78,8 @@ void UdpMinDelaySensor::localAck(char *packetData, int Len,int overheadLen, unsi
 	// Send an event message to the monitor to change the value of minimum one way delay.
 	if(eventFlag == true)
 	{
-		cout << "New Min delay = " << minDelay << "\n";
+		logStream << "VALUE::New Min delay = " << minDelay << "\n";
 	}
-	outStream << "MIND:TIME="<<timeStamp<<",MIND="<<minDelay<<endl;
+	logStream << "MIND:TIME="<<timeStamp<<",MIND="<<minDelay<<endl;
 	udpStateInfo.minDelay = minDelay;
 }

pelab/magent/UDP/UdpClientDir/UdpMinDelaySensor.h

@@ -10,14 +10,17 @@ class UdpSensor;
 class UdpMinDelaySensor:public UdpSensor{
 	public:
 
-		explicit UdpMinDelaySensor(UdpState &udpStateVal, ofstream &outStreamVal);
+		explicit UdpMinDelaySensor(UdpState &udpStateVal, ofstream &logStreamVal);
+		~UdpMinDelaySensor();
+
+
 		void localSend(char *packetData, int Len,int overheadLen, unsigned long long timeStamp);
 		void localAck(char *packetData, int Len,int overheadLen, unsigned long long timeStamp);
 
 	private:
 		unsigned long long minDelay;
 		UdpState &udpStateInfo;
-		ofstream &outStream;
+		ofstream &logStream;
 };
 
 #endif

pelab/magent/UDP/UdpClientDir/UdpPacketInfo.cc

@@ -11,3 +11,8 @@ UdpPacketInfo::UdpPacketInfo(unsigned short int seqVal,unsigned short int packet
 {
 
 }
+
+UdpPacketInfo::~UdpPacketInfo()
+{
+
+}

pelab/magent/UDP/UdpClientDir/UdpPacketInfo.h

@@ -3,8 +3,10 @@
 
 class UdpPacketInfo{
         public:
-	UdpPacketInfo::UdpPacketInfo();
-	UdpPacketInfo::UdpPacketInfo(unsigned short int, unsigned short int, unsigned long long);
+	UdpPacketInfo();
+	UdpPacketInfo(unsigned short int, unsigned short int, unsigned long long);
+	~UdpPacketInfo();
+
         unsigned short int seqNum;
         unsigned short int packetSize;
         unsigned long long timeStamp;

pelab/magent/UDP/UdpClientDir/UdpPacketSensor.cc

 #include "UdpPacketSensor.h"
 
-UdpPacketSensor::UdpPacketSensor(UdpState &udpStateVal)
+UdpPacketSensor::UdpPacketSensor(UdpState &udpStateVal, ofstream &logStreamVal)
 	:udpStateInfo(udpStateVal),
-	lastSeenSeqNum(-1)
+	lastSeenSeqNum(-1),
+	logStream(logStreamVal)
 {
 
 }
@@ -20,7 +21,7 @@ void UdpPacketSensor::localSend(char *packetData, int Len, int overheadLen, unsi
 
 	if(Len < minSize)
 	{
-		cout << "Error: UDP packet data sent to PacketSensor::localSend was less than the "
+		logStream << "ERROR::UDP packet data sent to PacketSensor::localSend was less than the "
 			" required minimum "<< minSize << " bytes\n";
 		return;
 	}
@@ -43,6 +44,7 @@ void UdpPacketSensor::localSend(char *packetData, int Len, int overheadLen, unsi
 
 				sentPacketList.push_back(tmpPacketInfo);
 			}
+			udpStateInfo.libpcapSendLoss += (seqNum - lastSeenSeqNum - 1);
 		}
 	}
 
@@ -60,7 +62,7 @@ void UdpPacketSensor::localAck(char *packetData, int Len, int overheadLen, unsig
 {
 	if(Len < globalConsts::minAckPacketSize)
 	{
-		cout << "Error: UDP packet data sent to PacketSensor::localAck was less than the "
+		logStream << "ERROR::UDP packet data sent to PacketSensor::localAck was less than the "
 			" minimum "<< globalConsts::minAckPacketSize << " bytes\n";
 		return;
 	}
@@ -75,7 +77,7 @@ void UdpPacketSensor::localAck(char *packetData, int Len, int overheadLen, unsig
 
 	if(listIterator == sentPacketList.end())
 	{
-		cout << "WARNING: Unknown seq number "<<seqNum<<" is being ACKed. "
+		logStream << "WARNING::Unknown seq number "<<seqNum<<" is being ACKed. "
 			"We might have received "
 			" a reordered ACK, which has already been ACKed using redundant ACKs .\n";
 		udpStateInfo.ackError = true;
@@ -158,18 +160,21 @@ void UdpPacketSensor::localAck(char *packetData, int Len, int overheadLen, unsig
 
 	if( (listIterator != sentPacketList.end()) && (listIterator != curPacketIterator ))
 	{
+		logStream<<"STAT::Packet being ACKed = "<<seqNum<<endl;
 
 		do{
+			logStream<<"STAT::Lost packet seqnum = "<<(*listIterator).seqNum<<endl;
 			sentPacketList.erase(listIterator);
 			listIterator = sentPacketList.end();
 
 			udpStateInfo.packetLoss++;
+			udpStateInfo.totalPacketLoss++;
 
 			listIterator = find_if(sentPacketList.begin(), curPacketIterator, bind2nd(lessSeqNum(), seqNum )); 
 
 		}