From 8dfba586faa8ebee05d9aa48217c484e6f2d0bf6 Mon Sep 17 00:00:00 2001 From: michele papalini Date: Fri, 18 Oct 2019 13:56:07 +0200 Subject: [HICN-337] correlty set timers for rtx in rtc consumer Signed-off-by: michele papalini Change-Id: Iaf947ac6c7763ba0a648f9cc865ca0f11cb3e31f --- libtransport/src/hicn/transport/protocols/rtc.cc | 75 ++++++++++++++++-------- libtransport/src/hicn/transport/protocols/rtc.h | 3 + 2 files changed, 54 insertions(+), 24 deletions(-) (limited to 'libtransport/src/hicn') diff --git a/libtransport/src/hicn/transport/protocols/rtc.cc b/libtransport/src/hicn/transport/protocols/rtc.cc index ba8f549c3..7858c4017 100644 --- a/libtransport/src/hicn/transport/protocols/rtc.cc +++ b/libtransport/src/hicn/transport/protocols/rtc.cc @@ -87,6 +87,9 @@ void RTCTransportProtocol::reset() { interestRetransmissions_.clear(); lastSegNacked_ = 0; lastReceived_ = 0; + lastReceivedTime_ = std::chrono::duration_cast( + std::chrono::steady_clock::now().time_since_epoch()) + .count(); highestReceived_ = 0; firstSequenceInRound_ = 0; @@ -205,7 +208,7 @@ void RTCTransportProtocol::updateStats(uint32_t round_duration) { ((1 - HICN_ESTIMATED_BW_ALPHA) * bytesPerSec); } - uint64_t minRtt = 150; + uint64_t minRtt = UINT_MAX; uint64_t maxRtt = 0; for (auto it = pathTable_.begin(); it != pathTable_.end(); it++) { @@ -228,7 +231,7 @@ void RTCTransportProtocol::updateStats(uint32_t round_duration) { //as a queuing delay we keep the lowest one among the two paths //if one path is congested the forwarder should decide to do not - //use it soon so it does not make sens to inform the application + //use it so it does not make sense to inform the application //that maybe we have a problem if(pathTable_[producerPathLabels_[0]]->getQueuingDealy() < pathTable_[producerPathLabels_[1]]->getQueuingDealy()) @@ -506,6 +509,7 @@ void RTCTransportProtocol::addRetransmissions(uint32_t start, uint32_t stop) { std::chrono::steady_clock::now().time_since_epoch()) .count(); + bool new_rtx = false; for (uint32_t i = start; i < stop; i++) { auto it = interestRetransmissions_.find(i); if (it == interestRetransmissions_.end()) { @@ -519,13 +523,21 @@ void RTCTransportProtocol::addRetransmissions(uint32_t start, uint32_t stop) { //we reset the transmission time setting to now, so that rtx will //happne in one RTT on waint one inter arrival gap inflightInterests_[pkt].transmissionTime = now; + new_rtx = true; } } // if the retransmission is already there the rtx timer will // take care of it } - if(!rtx_timer_used_) + //in case a new rtx is added to the map we need to run checkRtx() + if(new_rtx){ + if(rtx_timer_used_){ + //if a timer is pending we need to delete it + rtx_timer_->cancel(); + rtx_timer_used_ = false; + } checkRtx(); + } } uint64_t RTCTransportProtocol::retransmit() { @@ -540,6 +552,9 @@ uint64_t RTCTransportProtocol::retransmit() { it = interestRetransmissions_.begin(); uint64_t smallest_timeout = ULONG_MAX; + uint64_t now = std::chrono::duration_cast( + std::chrono::steady_clock::now().time_since_epoch()) + .count(); while (it != interestRetransmissions_.end()) { uint32_t pkt = it->first & modMask_; @@ -563,31 +578,38 @@ uint64_t RTCTransportProtocol::retransmit() { continue; } - - uint64_t sent_time = inflightInterests_[pkt].transmissionTime; - uint64_t rtx_time = sent_time; - - if(it->second == 0 && - pathTable_.find(producerPathLabels_[0]) != pathTable_.end() && - (pathTable_[producerPathLabels_[0]]->getInterArrivalGap() < - pathTable_[producerPathLabels_[0]]->getMinRtt())){ - if(pathTable_.find(producerPathLabels_[1]) != pathTable_.end()){ - //first rtx: wait RTTmax - RTTmin + gap - rtx_time = sent_time + pathTable_[producerPathLabels_[1]]->getMinRtt() - - pathTable_[producerPathLabels_[0]]->getMinRtt() + - pathTable_[producerPathLabels_[0]]->getInterArrivalGap(); + uint64_t rtx_time = now; + + if(it->second == 0) { + //first rtx + if(producerPathLabels_[0] != producerPathLabels_[1]){ + //multipath + if(pathTable_.find(producerPathLabels_[0]) != pathTable_.end() && + pathTable_.find(producerPathLabels_[1]) != pathTable_.end() && + (pathTable_[producerPathLabels_[0]]->getInterArrivalGap() < + HICN_MIN_INTER_ARRIVAL_GAP)){ + rtx_time = lastReceivedTime_ + + (pathTable_[producerPathLabels_[1]]->getMinRtt() - + pathTable_[producerPathLabels_[0]]->getMinRtt()) + + pathTable_[producerPathLabels_[0]]->getInterArrivalGap(); + }//else low rate producer, send it immediatly + }else{ + //single path + if(pathTable_.find(producerPathLabels_[0]) != pathTable_.end() && + (pathTable_[producerPathLabels_[0]]->getInterArrivalGap() < + HICN_MIN_INTER_ARRIVAL_GAP)){ + rtx_time = lastReceivedTime_ + + pathTable_[producerPathLabels_[0]]->getInterArrivalGap(); + }//else low rate producer send immediatly } }else{ + //second or plus rtx, wait for the min rtt if(pathTable_.find(producerPathLabels_[0]) != pathTable_.end()){ - //second+ rtx: wait min rtt + uint64_t sent_time = inflightInterests_[pkt].transmissionTime; rtx_time = sent_time + pathTable_[producerPathLabels_[0]]->getMinRtt(); - } + }//if we don't have info we send it immediatly } - uint64_t now = std::chrono::duration_cast( - std::chrono::steady_clock::now().time_since_epoch()) - .count(); - if(now >= rtx_time){ inflightInterests_[pkt].transmissionTime = now; it->second++; @@ -612,7 +634,6 @@ void RTCTransportProtocol::checkRtx() { return; } - rtx_timer_used_ = true; uint64_t next_timeout = retransmit(); uint64_t wait = 1; uint64_t now = std::chrono::duration_cast( @@ -621,9 +642,11 @@ void RTCTransportProtocol::checkRtx() { if(next_timeout != ULONG_MAX && now < next_timeout){ wait = next_timeout - now; } + rtx_timer_used_ = true; rtx_timer_->expires_from_now(std::chrono::milliseconds(wait)); rtx_timer_->async_wait([this](std::error_code ec) { if (ec) return; + rtx_timer_used_ = false; checkRtx(); }); } @@ -822,7 +845,11 @@ void RTCTransportProtocol::onContentObject( highestReceived_ = segmentNumber; } if(segmentNumber > lastReceived_){ - lastReceived_ = segmentNumber; + lastReceived_ = segmentNumber; + lastReceivedTime_ = std::chrono::duration_cast< + std::chrono::milliseconds>( + std::chrono::steady_clock::now().time_since_epoch()) + .count(); } receivedData_++; inflightInterests_[pkt].state = received_; diff --git a/libtransport/src/hicn/transport/protocols/rtc.h b/libtransport/src/hicn/transport/protocols/rtc.h index cac885bc4..7927e3969 100644 --- a/libtransport/src/hicn/transport/protocols/rtc.h +++ b/libtransport/src/hicn/transport/protocols/rtc.h @@ -49,6 +49,7 @@ #define HICN_MAX_RTX_SIZE 1024 #define HICN_MAX_RTX_MAX_AGE 10000 #define HICN_MIN_RTT_WIN 30 // rounds +#define HICN_MIN_INTER_ARRIVAL_GAP 100 //ms // cwin #define HICN_INITIAL_CWIN 1 // packets @@ -159,6 +160,8 @@ class RTCTransportProtocol : public TransportProtocol, public Reassembly { //for samething that is older than this value. uint32_t lastReceived_; //segment of the last content object received //indicates the base of the window on the client + uint64_t lastReceivedTime_; //time at which we recevied the + //lastReceived_ packet //rtt probes //the RTC transport tends to overestimate the RTT -- cgit 1.2.3-korg