ZeroTierOne/node/Bond.cpp

1807 lines
69 KiB
C++

/*
* Copyright (c)2013-2020 ZeroTier, Inc.
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file in the project's root directory.
*
* Change Date: 2025-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2.0 of the Apache License.
*/
/****/
#include <cmath>
#include "../osdep/OSUtils.hpp"
#include "Peer.hpp"
#include "Bond.hpp"
#include "Switch.hpp"
#include "Flow.hpp"
#include "Path.hpp"
namespace ZeroTier {
Bond::Bond(const RuntimeEnvironment *renv, int policy, const SharedPtr<Peer>& peer) :
RR(renv),
_peer(peer),
_qosCutoffCount(0),
_ackCutoffCount(0),
_lastAckRateCheck(0),
_lastQoSRateCheck(0),
_lastQualityEstimation(0),
_lastCheckUserPreferences(0),
_lastBackgroundTaskCheck(0),
_lastBondStatusLog(0),
_lastPathNegotiationReceived(0),
_lastPathNegotiationCheck(0),
_lastSentPathNegotiationRequest(0),
_lastFlowStatReset(0),
_lastFlowExpirationCheck(0),
_lastFlowRebalance(0),
_lastFrame(0),
_lastActiveBackupPathChange(0)
{
setReasonableDefaults(policy, SharedPtr<Bond>(), false);
_policyAlias = BondController::getPolicyStrByCode(policy);
}
Bond::Bond(const RuntimeEnvironment *renv, std::string& basePolicy, std::string& policyAlias, const SharedPtr<Peer>& peer) :
RR(renv),
_policyAlias(policyAlias),
_peer(peer)
{
setReasonableDefaults(BondController::getPolicyCodeByStr(basePolicy), SharedPtr<Bond>(), false);
}
Bond::Bond(const RuntimeEnvironment *renv, SharedPtr<Bond> originalBond, const SharedPtr<Peer>& peer) :
RR(renv),
_peer(peer),
_lastAckRateCheck(0),
_lastQoSRateCheck(0),
_lastQualityEstimation(0),
_lastCheckUserPreferences(0),
_lastBackgroundTaskCheck(0),
_lastBondStatusLog(0),
_lastPathNegotiationReceived(0),
_lastPathNegotiationCheck(0),
_lastFlowStatReset(0),
_lastFlowExpirationCheck(0),
_lastFlowRebalance(0),
_lastFrame(0)
{
setReasonableDefaults(originalBond->_bondingPolicy, originalBond, true);
}
void Bond::nominatePath(const SharedPtr<Path>& path, int64_t now)
{
char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
Mutex::Lock _l(_paths_m);
if (!RR->bc->linkAllowed(_policyAlias, getLink(path))) {
return;
}
bool alreadyPresent = false;
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (path.ptr() == _paths[i].ptr()) {
// Previously encountered path, not notifying bond
alreadyPresent = true;
break;
}
}
if (!alreadyPresent) {
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (!_paths[i]) {
_paths[i] = path;
sprintf(traceMsg, "%s (bond) Nominating link %s/%s to peer %llx. It has now entered its trial period",
OSUtils::humanReadableTimestamp().c_str(), getLink(path)->ifname().c_str(), pathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
_paths[i]->startTrial(now);
break;
}
}
}
curateBond(now, true);
estimatePathQuality(now);
}
SharedPtr<Path> Bond::getAppropriatePath(int64_t now, int32_t flowId)
{
Mutex::Lock _l(_paths_m);
/**
* active-backup
*/
if (_bondingPolicy == ZT_BONDING_POLICY_ACTIVE_BACKUP) {
if (_abPath) {
return _abPath;
}
}
/**
* broadcast
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BROADCAST) {
return SharedPtr<Path>(); // Handled in Switch::_trySend()
}
if (!_numBondedPaths) {
return SharedPtr<Path>(); // No paths assigned to bond yet, cannot balance traffic
}
/**
* balance-rr
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR) {
if (!_allowFlowHashing) {
if (_packetsPerLink == 0) {
// Randomly select a path
return _paths[_bondedIdx[_freeRandomByte % _numBondedPaths]]; // TODO: Optimize
}
if (_rrPacketsSentOnCurrLink < _packetsPerLink) {
// Continue to use this link
++_rrPacketsSentOnCurrLink;
return _paths[_bondedIdx[_rrIdx]];
}
// Reset striping counter
_rrPacketsSentOnCurrLink = 0;
if (_numBondedPaths == 1) {
_rrIdx = 0;
}
else {
int _tempIdx = _rrIdx;
for (int searchCount = 0; searchCount < (_numBondedPaths-1); searchCount++) {
_tempIdx = (_tempIdx == (_numBondedPaths-1)) ? 0 : _tempIdx+1;
if (_bondedIdx[_tempIdx] != ZT_MAX_PEER_NETWORK_PATHS) {
if (_paths[_bondedIdx[_tempIdx]] && _paths[_bondedIdx[_tempIdx]]->eligible(now,_ackSendInterval)) {
_rrIdx = _tempIdx;
break;
}
}
}
}
if (_paths[_bondedIdx[_rrIdx]]) {
return _paths[_bondedIdx[_rrIdx]];
}
}
}
/**
* balance-xor
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR || _bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
if (!_allowFlowHashing || flowId == -1) {
// No specific path required for unclassified traffic, send on anything
return _paths[_bondedIdx[_freeRandomByte % _numBondedPaths]]; // TODO: Optimize
}
else if (_allowFlowHashing) {
// TODO: Optimize
Mutex::Lock _l(_flows_m);
SharedPtr<Flow> flow;
if (_flows.count(flowId)) {
flow = _flows[flowId];
flow->updateActivity(now);
}
else {
unsigned char entropy;
Utils::getSecureRandom(&entropy, 1);
flow = createFlow(SharedPtr<Path>(), flowId, entropy, now);
}
if (flow) {
return flow->assignedPath();
}
}
}
return SharedPtr<Path>();
}
void Bond::recordIncomingInvalidPacket(const SharedPtr<Path>& path)
{
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (qos) Invalid packet on link %s/%s from peer %llx",
// OSUtils::humanReadableTimestamp().c_str(), getLink(path)->ifname().c_str(), pathStr, _peer->_id.address().toInt());
//RR->t->bondStateMessage(NULL, traceMsg);
Mutex::Lock _l(_paths_m);
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (_paths[i] == path) {
_paths[i]->packetValiditySamples.push(false);
}
}
}
void Bond::recordOutgoingPacket(const SharedPtr<Path> &path, const uint64_t packetId,
uint16_t payloadLength, const Packet::Verb verb, const int32_t flowId, int64_t now)
{
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (bond) Outgoing packet on link %s/%s to peer %llx",
// OSUtils::humanReadableTimestamp().c_str(), getLink(path)->ifname().c_str(), pathStr, _peer->_id.address().toInt());
//RR->t->bondStateMessage(NULL, traceMsg);
_freeRandomByte += (unsigned char)(packetId >> 8); // Grab entropy to use in path selection logic
if (!_shouldCollectPathStatistics) {
return;
}
bool isFrame = (verb == Packet::VERB_FRAME || verb == Packet::VERB_EXT_FRAME);
bool shouldRecord = (packetId & (ZT_QOS_ACK_DIVISOR - 1)
&& (verb != Packet::VERB_ACK)
&& (verb != Packet::VERB_QOS_MEASUREMENT));
if (isFrame || shouldRecord) {
Mutex::Lock _l(_paths_m);
if (isFrame) {
++(path->_packetsOut);
_lastFrame=now;
}
if (shouldRecord) {
path->_unackedBytes += payloadLength;
// Take note that we're expecting a VERB_ACK on this path as of a specific time
if (path->qosStatsOut.size() < ZT_QOS_MAX_OUTSTANDING_RECORDS) {
path->qosStatsOut[packetId] = now;
}
}
}
if (_allowFlowHashing) {
if (_allowFlowHashing && (flowId != ZT_QOS_NO_FLOW)) {
Mutex::Lock _l(_flows_m);
if (_flows.count(flowId)) {
_flows[flowId]->recordOutgoingBytes(payloadLength);
}
}
}
}
void Bond::recordIncomingPacket(const SharedPtr<Path>& path, uint64_t packetId, uint16_t payloadLength,
Packet::Verb verb, int32_t flowId, int64_t now)
{
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (bond) Incoming packet on link %s/%s from peer %llx [id=%llx, len=%d, verb=%d, flowId=%x]",
// OSUtils::humanReadableTimestamp().c_str(), getLink(path)->ifname().c_str(), pathStr, _peer->_id.address().toInt(), packetId, payloadLength, verb, flowId);
//RR->t->bondStateMessage(NULL, traceMsg);
bool isFrame = (verb == Packet::VERB_FRAME || verb == Packet::VERB_EXT_FRAME);
bool shouldRecord = (packetId & (ZT_QOS_ACK_DIVISOR - 1)
&& (verb != Packet::VERB_ACK)
&& (verb != Packet::VERB_QOS_MEASUREMENT));
if (isFrame || shouldRecord) {
Mutex::Lock _l(_paths_m);
if (isFrame) {
++(path->_packetsIn);
_lastFrame=now;
}
if (shouldRecord) {
path->ackStatsIn[packetId] = payloadLength;
++(path->_packetsReceivedSinceLastAck);
path->qosStatsIn[packetId] = now;
++(path->_packetsReceivedSinceLastQoS);
path->packetValiditySamples.push(true);
}
}
/**
* Learn new flows and pro-actively create entries for them in the bond so
* that the next time we send a packet out that is part of a flow we know
* which path to use.
*/
if ((flowId != ZT_QOS_NO_FLOW)
&& (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR
|| _bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR
|| _bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE)) {
Mutex::Lock _l(_flows_m);
SharedPtr<Flow> flow;
if (!_flows.count(flowId)) {
flow = createFlow(path, flowId, 0, now);
} else {
flow = _flows[flowId];
}
if (flow) {
flow->recordIncomingBytes(payloadLength);
}
}
}
void Bond::receivedQoS(const SharedPtr<Path>& path, int64_t now, int count, uint64_t *rx_id, uint16_t *rx_ts)
{
Mutex::Lock _l(_paths_m);
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (qos) Received QoS packet sampling %d frames from peer %llx via %s/%s",
// OSUtils::humanReadableTimestamp().c_str(), count, _peer->_id.address().toInt(), getLink(path)->ifname().c_str(), pathStr);
//RR->t->bondStateMessage(NULL, traceMsg);
// Look up egress times and compute latency values for each record
std::map<uint64_t,uint64_t>::iterator it;
for (int j=0; j<count; j++) {
it = path->qosStatsOut.find(rx_id[j]);
if (it != path->qosStatsOut.end()) {
path->latencySamples.push(((uint16_t)(now - it->second) - rx_ts[j]) / 2);
path->qosStatsOut.erase(it);
}
}
path->qosRecordSize.push(count);
}
void Bond::receivedAck(const SharedPtr<Path>& path, int64_t now, int32_t ackedBytes)
{
Mutex::Lock _l(_paths_m);
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (qos) Received ACK packet for %d bytes from peer %llx via %s/%s",
// OSUtils::humanReadableTimestamp().c_str(), ackedBytes, _peer->_id.address().toInt(), getLink(path)->ifname().c_str(), pathStr);
//RR->t->bondStateMessage(NULL, traceMsg);
path->_lastAckReceived = now;
path->_unackedBytes = (ackedBytes > path->_unackedBytes) ? 0 : path->_unackedBytes - ackedBytes;
int64_t timeSinceThroughputEstimate = (now - path->_lastThroughputEstimation);
if (timeSinceThroughputEstimate >= throughputMeasurementInterval) {
// TODO: See if this floating point math can be reduced
uint64_t throughput = (uint64_t)((float)(path->_bytesAckedSinceLastThroughputEstimation) / ((float)timeSinceThroughputEstimate / (float)1000));
throughput /= 1000;
if (throughput > 0.0) {
path->throughputSamples.push(throughput);
path->_throughputMax = throughput > path->_throughputMax ? throughput : path->_throughputMax;
}
path->_lastThroughputEstimation = now;
path->_bytesAckedSinceLastThroughputEstimation = 0;
} else {
path->_bytesAckedSinceLastThroughputEstimation += ackedBytes;
}
}
int32_t Bond::generateQoSPacket(const SharedPtr<Path>& path, int64_t now, char *qosBuffer)
{
int32_t len = 0;
std::map<uint64_t,uint64_t>::iterator it = path->qosStatsIn.begin();
int i=0;
int numRecords = std::min(path->_packetsReceivedSinceLastQoS,ZT_QOS_TABLE_SIZE);
while (i<numRecords && it != path->qosStatsIn.end()) {
uint64_t id = it->first;
memcpy(qosBuffer, &id, sizeof(uint64_t));
qosBuffer+=sizeof(uint64_t);
uint16_t holdingTime = (uint16_t)(now - it->second);
memcpy(qosBuffer, &holdingTime, sizeof(uint16_t));
qosBuffer+=sizeof(uint16_t);
len+=sizeof(uint64_t)+sizeof(uint16_t);
path->qosStatsIn.erase(it++);
++i;
}
return len;
}
bool Bond::assignFlowToBondedPath(SharedPtr<Flow> &flow, int64_t now)
{
char traceMsg[256];
char curPathStr[128];
unsigned int idx = ZT_MAX_PEER_NETWORK_PATHS;
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR) {
idx = abs((int)(flow->id() % (_numBondedPaths)));
SharedPtr<Link> link = RR->bc->getLinkBySocket(_policyAlias, _paths[_bondedIdx[idx]]->localSocket());
_paths[_bondedIdx[idx]]->address().toString(curPathStr);
sprintf(traceMsg, "%s (balance-xor) Assigned outgoing flow %x to peer %llx to link %s/%s, %lu active flow(s)",
OSUtils::humanReadableTimestamp().c_str(), flow->id(), _peer->_id.address().toInt(), link->ifname().c_str(), curPathStr, _flows.size());
RR->t->bondStateMessage(NULL, traceMsg);
flow->assignPath(_paths[_bondedIdx[idx]],now);
++(_paths[_bondedIdx[idx]]->_assignedFlowCount);
}
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
unsigned char entropy;
Utils::getSecureRandom(&entropy, 1);
if (_totalBondUnderload) {
entropy %= _totalBondUnderload;
}
if (!_numBondedPaths) {
sprintf(traceMsg, "%s (balance-aware) There are no bonded paths, cannot assign flow %x\n",
OSUtils::humanReadableTimestamp().c_str(), flow->id());
RR->t->bondStateMessage(NULL, traceMsg);
return false;
}
/* Since there may be scenarios where a path is removed before we can re-estimate
relative qualities (and thus allocations) we need to down-modulate the entropy
value that we use to randomly assign among the surviving paths, otherwise we risk
not being able to find a path to assign this flow to. */
int totalIncompleteAllocation = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i] && _paths[i]->bonded()) {
totalIncompleteAllocation += _paths[i]->_allocation;
}
}
entropy %= totalIncompleteAllocation;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i] && _paths[i]->bonded()) {
SharedPtr<Link> link = RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
_paths[i]->address().toString(curPathStr);
uint8_t probabilitySegment = (_totalBondUnderload > 0) ? _paths[i]->_affinity : _paths[i]->_allocation;
if (entropy <= probabilitySegment) {
idx = i;
break;
}
entropy -= probabilitySegment;
}
}
if (idx < ZT_MAX_PEER_NETWORK_PATHS) {
if (flow->_assignedPath) {
flow->_previouslyAssignedPath = flow->_assignedPath;
}
flow->assignPath(_paths[idx],now);
++(_paths[idx]->_assignedFlowCount);
}
else {
fprintf(stderr, "could not assign flow?\n"); exit(0); // TODO: Remove for production
return false;
}
}
flow->assignedPath()->address().toString(curPathStr);
SharedPtr<Link> link = RR->bc->getLinkBySocket(_policyAlias, flow->assignedPath()->localSocket());
sprintf(traceMsg, "%s (bond) Assigned outgoing flow %x to peer %llx to link %s/%s, %lu active flow(s)",
OSUtils::humanReadableTimestamp().c_str(), flow->id(), _peer->_id.address().toInt(), link->ifname().c_str(), curPathStr, _flows.size());
RR->t->bondStateMessage(NULL, traceMsg);
return true;
}
SharedPtr<Flow> Bond::createFlow(const SharedPtr<Path> &path, int32_t flowId, unsigned char entropy, int64_t now)
{
char traceMsg[256];
char curPathStr[128];
// ---
if (!_numBondedPaths) {
sprintf(traceMsg, "%s (bond) There are no bonded paths to peer %llx, cannot assign flow %x\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), flowId);
RR->t->bondStateMessage(NULL, traceMsg);
return SharedPtr<Flow>();
}
if (_flows.size() >= ZT_FLOW_MAX_COUNT) {
sprintf(traceMsg, "%s (bond) Maximum number of flows on bond to peer %llx reached (%d), forcibly forgetting oldest flow\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), ZT_FLOW_MAX_COUNT);
RR->t->bondStateMessage(NULL, traceMsg);
forgetFlowsWhenNecessary(0, true, now);
}
SharedPtr<Flow> flow = new Flow(flowId, now);
_flows[flowId] = flow;
/**
* Add a flow with a given Path already provided. This is the case when a packet
* is received on a path but no flow exists, in this case we simply assign the path
* that the remote peer chose for us.
*/
if (path) {
flow->assignPath(path,now);
path->address().toString(curPathStr);
path->_assignedFlowCount++;
SharedPtr<Link> link = RR->bc->getLinkBySocket(_policyAlias, flow->assignedPath()->localSocket());
sprintf(traceMsg, "%s (bond) Assigned incoming flow %x from peer %llx to link %s/%s, %lu active flow(s)",
OSUtils::humanReadableTimestamp().c_str(), flow->id(), _peer->_id.address().toInt(), link->ifname().c_str(), curPathStr, _flows.size());
RR->t->bondStateMessage(NULL, traceMsg);
}
/**
* Add a flow when no path was provided. This means that it is an outgoing packet
* and that it is up to the local peer to decide how to load-balance its transmission.
*/
else if (!path) {
assignFlowToBondedPath(flow, now);
}
return flow;
}
void Bond::forgetFlowsWhenNecessary(uint64_t age, bool oldest, int64_t now)
{
char traceMsg[256];
std::map<int32_t,SharedPtr<Flow> >::iterator it = _flows.begin();
std::map<int32_t,SharedPtr<Flow> >::iterator oldestFlow = _flows.end();
SharedPtr<Flow> expiredFlow;
if (age) { // Remove by specific age
while (it != _flows.end()) {
if (it->second->age(now) > age) {
sprintf(traceMsg, "%s (bond) Forgetting flow %x between this node and peer %llx, %lu active flow(s)",
OSUtils::humanReadableTimestamp().c_str(), it->first, _peer->_id.address().toInt(), (_flows.size()-1));
RR->t->bondStateMessage(NULL, traceMsg);
it->second->assignedPath()->_assignedFlowCount--;
it = _flows.erase(it);
} else {
++it;
}
}
}
else if (oldest) { // Remove single oldest by natural expiration
uint64_t maxAge = 0;
while (it != _flows.end()) {
if (it->second->age(now) > maxAge) {
maxAge = (now - it->second->age(now));
oldestFlow = it;
}
++it;
}
if (oldestFlow != _flows.end()) {
sprintf(traceMsg, "%s (bond) Forgetting oldest flow %x (of age %llu) between this node and peer %llx, %lu active flow(s)",
OSUtils::humanReadableTimestamp().c_str(), oldestFlow->first, oldestFlow->second->age(now), _peer->_id.address().toInt(), (_flows.size()-1));
RR->t->bondStateMessage(NULL, traceMsg);
oldestFlow->second->assignedPath()->_assignedFlowCount--;
_flows.erase(oldestFlow);
}
}
}
void Bond::processIncomingPathNegotiationRequest(uint64_t now, SharedPtr<Path> &path, int16_t remoteUtility)
{
char traceMsg[256];
if (_abLinkSelectMethod != ZT_MULTIPATH_RESELECTION_POLICY_OPTIMIZE) {
return;
}
Mutex::Lock _l(_paths_m);
char pathStr[128];
path->address().toString(pathStr);
if (!_lastPathNegotiationCheck) {
return;
}
SharedPtr<Link> link = RR->bc->getLinkBySocket(_policyAlias, path->localSocket());
if (remoteUtility > _localUtility) {
char pathStr[128]; path->address().toString(pathStr);
sprintf(traceMsg, "%s (bond) Peer %llx suggests using alternate link %s/%s. Remote utility (%d) is GREATER than local utility (%d), switching to said link\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), link->ifname().c_str(), pathStr, remoteUtility, _localUtility);
RR->t->bondStateMessage(NULL, traceMsg);
negotiatedPath = path;
}
if (remoteUtility < _localUtility) {
sprintf(traceMsg, "%s (bond) Peer %llx suggests using alternate link %s/%s. Remote utility (%d) is LESS than local utility (%d), not switching\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), link->ifname().c_str(), pathStr, remoteUtility, _localUtility);
RR->t->bondStateMessage(NULL, traceMsg);
}
if (remoteUtility == _localUtility) {
sprintf(traceMsg, "%s (bond) Peer %llx suggests using alternate link %s/%s. Remote utility (%d) is equal to local utility (%d)\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), link->ifname().c_str(), pathStr, remoteUtility, _localUtility);
RR->t->bondStateMessage(NULL, traceMsg);
if (_peer->_id.address().toInt() > RR->node->identity().address().toInt()) {
sprintf(traceMsg, "%s (bond) Agreeing with peer %llx to use alternate link %s/%s\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), link->ifname().c_str(), pathStr);
RR->t->bondStateMessage(NULL, traceMsg);
negotiatedPath = path;
} else {
sprintf(traceMsg, "%s (bond) Ignoring petition from peer %llx to use alternate link %s/%s\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), link->ifname().c_str(), pathStr);
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
void Bond::pathNegotiationCheck(void *tPtr, const int64_t now)
{
char pathStr[128];
int maxInPathIdx = ZT_MAX_PEER_NETWORK_PATHS;
int maxOutPathIdx = ZT_MAX_PEER_NETWORK_PATHS;
uint64_t maxInCount = 0;
uint64_t maxOutCount = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i]) {
continue;
}
if (_paths[i]->_packetsIn > maxInCount) {
maxInCount = _paths[i]->_packetsIn;
maxInPathIdx = i;
}
if (_paths[i]->_packetsOut > maxOutCount) {
maxOutCount = _paths[i]->_packetsOut;
maxOutPathIdx = i;
}
_paths[i]->resetPacketCounts();
}
bool _peerLinksSynchronized = ((maxInPathIdx != ZT_MAX_PEER_NETWORK_PATHS)
&& (maxOutPathIdx != ZT_MAX_PEER_NETWORK_PATHS)
&& (maxInPathIdx != maxOutPathIdx)) ? false : true;
/**
* Determine utility and attempt to petition remote peer to switch to our chosen path
*/
if (!_peerLinksSynchronized) {
_localUtility = _paths[maxOutPathIdx]->_failoverScore - _paths[maxInPathIdx]->_failoverScore;
if (_paths[maxOutPathIdx]->_negotiated) {
_localUtility -= ZT_MULTIPATH_FAILOVER_HANDICAP_NEGOTIATED;
}
if ((now - _lastSentPathNegotiationRequest) > ZT_PATH_NEGOTIATION_CUTOFF_TIME) {
//fprintf(stderr, "BT: (sync) it's been long enough, sending more requests.\n");
_numSentPathNegotiationRequests = 0;
}
if (_numSentPathNegotiationRequests < ZT_PATH_NEGOTIATION_TRY_COUNT) {
if (_localUtility >= 0) {
//fprintf(stderr, "BT: (sync) paths appear to be out of sync (utility=%d)\n", _localUtility);
sendPATH_NEGOTIATION_REQUEST(tPtr, _paths[maxOutPathIdx]);
++_numSentPathNegotiationRequests;
_lastSentPathNegotiationRequest = now;
_paths[maxOutPathIdx]->address().toString(pathStr);
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[maxOutPathIdx]->localSocket());
//fprintf(stderr, "sending request to use %s on %s, ls=%llx, utility=%d\n", pathStr, link->ifname().c_str(), _paths[maxOutPathIdx]->localSocket(), _localUtility);
}
}
/**
* Give up negotiating and consider switching
*/
else if ((now - _lastSentPathNegotiationRequest) > (2 * ZT_PATH_NEGOTIATION_CHECK_INTERVAL)) {
if (_localUtility == 0) {
// There's no loss to us, just switch without sending a another request
//fprintf(stderr, "BT: (sync) giving up, switching to remote peer's path.\n");
negotiatedPath = _paths[maxInPathIdx];
}
}
}
}
void Bond::sendPATH_NEGOTIATION_REQUEST(void *tPtr, const SharedPtr<Path> &path)
{
char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
sprintf(traceMsg, "%s (bond) Sending link negotiation request to peer %llx via link %s/%s, local utility is %d",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), getLink(path)->ifname().c_str(), pathStr, _localUtility);
RR->t->bondStateMessage(NULL, traceMsg);
if (_abLinkSelectMethod != ZT_MULTIPATH_RESELECTION_POLICY_OPTIMIZE) {
return;
}
Packet outp(_peer->_id.address(),RR->identity.address(),Packet::VERB_PATH_NEGOTIATION_REQUEST);
outp.append<int16_t>(_localUtility);
if (path->address()) {
outp.armor(_peer->key(),false,_peer->aesKeysIfSupported());
RR->node->putPacket(tPtr,path->localSocket(),path->address(),outp.data(),outp.size());
}
}
void Bond::sendACK(void *tPtr, const SharedPtr<Path> &path,const int64_t localSocket,
const InetAddress &atAddress,int64_t now)
{
Packet outp(_peer->_id.address(),RR->identity.address(),Packet::VERB_ACK);
int32_t bytesToAck = 0;
std::map<uint64_t,uint16_t>::iterator it = path->ackStatsIn.begin();
while (it != path->ackStatsIn.end()) {
bytesToAck += it->second;
++it;
}
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (qos) Sending ACK packet for %d bytes to peer %llx via link %s/%s",
// OSUtils::humanReadableTimestamp().c_str(), bytesToAck, _peer->_id.address().toInt(), getLink(path)->ifname().c_str(), pathStr);
//RR->t->bondStateMessage(NULL, traceMsg);
outp.append<uint32_t>(bytesToAck);
if (atAddress) {
outp.armor(_peer->key(),false,_peer->aesKeysIfSupported());
RR->node->putPacket(tPtr,localSocket,atAddress,outp.data(),outp.size());
} else {
RR->sw->send(tPtr,outp,false);
}
path->ackStatsIn.clear();
path->_packetsReceivedSinceLastAck = 0;
path->_lastAckSent = now;
}
void Bond::sendQOS_MEASUREMENT(void *tPtr,const SharedPtr<Path> &path,const int64_t localSocket,
const InetAddress &atAddress,int64_t now)
{
//char traceMsg[256]; char pathStr[128]; path->address().toString(pathStr);
//sprintf(traceMsg, "%s (qos) Sending QoS packet to peer %llx via link %s/%s",
// OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), getLink(path)->ifname().c_str(), pathStr);
//RR->t->bondStateMessage(NULL, traceMsg);
const int64_t _now = RR->node->now();
Packet outp(_peer->_id.address(),RR->identity.address(),Packet::VERB_QOS_MEASUREMENT);
char qosData[ZT_QOS_MAX_PACKET_SIZE];
int16_t len = generateQoSPacket(path, _now,qosData);
outp.append(qosData,len);
if (atAddress) {
outp.armor(_peer->key(),false,_peer->aesKeysIfSupported());
RR->node->putPacket(tPtr,localSocket,atAddress,outp.data(),outp.size());
} else {
RR->sw->send(tPtr,outp,false);
}
// Account for the fact that a VERB_QOS_MEASUREMENT was just sent. Reset timers.
path->_packetsReceivedSinceLastQoS = 0;
path->_lastQoSMeasurement = now;
}
void Bond::processBackgroundTasks(void *tPtr, const int64_t now)
{
Mutex::Lock _l(_paths_m);
if (!_peer->_canUseMultipath || (now - _lastBackgroundTaskCheck) < ZT_BOND_BACKGROUND_TASK_MIN_INTERVAL) {
return;
}
_lastBackgroundTaskCheck = now;
// Compute dynamic path monitor timer interval
if (_linkMonitorStrategy == ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_DYNAMIC) {
int suggestedMonitorInterval = (now - _lastFrame) / 100;
_dynamicPathMonitorInterval = std::min(ZT_PATH_HEARTBEAT_PERIOD, ((suggestedMonitorInterval > _bondMonitorInterval) ? suggestedMonitorInterval : _bondMonitorInterval));
}
// TODO: Clarify and generalize this logic
if (_linkMonitorStrategy == ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_DYNAMIC) {
_shouldCollectPathStatistics = true;
}
// Memoize oft-used properties in the packet ingress/egress logic path
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
// Required for real-time balancing
_shouldCollectPathStatistics = true;
}
if (_bondingPolicy == ZT_BONDING_POLICY_ACTIVE_BACKUP) {
if (_abLinkSelectMethod == ZT_MULTIPATH_RESELECTION_POLICY_BETTER) {
// Required for judging suitability of primary link after recovery
_shouldCollectPathStatistics = true;
}
if (_abLinkSelectMethod == ZT_MULTIPATH_RESELECTION_POLICY_OPTIMIZE) {
// Required for judging suitability of new candidate primary
_shouldCollectPathStatistics = true;
}
}
if ((now - _lastCheckUserPreferences) > 1000) {
_lastCheckUserPreferences = now;
applyUserPrefs();
}
curateBond(now,false);
if ((now - _lastQualityEstimation) > _qualityEstimationInterval) {
_lastQualityEstimation = now;
estimatePathQuality(now);
}
dumpInfo(now);
// Send QOS/ACK packets as needed
if (_shouldCollectPathStatistics) {
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i] && _paths[i]->allowed()) {
if (_paths[i]->needsToSendQoS(now,_qosSendInterval)) {
sendQOS_MEASUREMENT(tPtr, _paths[i], _paths[i]->localSocket(), _paths[i]->address(), now);
}
if (_paths[i]->needsToSendAck(now,_ackSendInterval)) {
sendACK(tPtr, _paths[i], _paths[i]->localSocket(), _paths[i]->address(), now);
}
}
}
}
// Perform periodic background tasks unique to each bonding policy
switch (_bondingPolicy)
{
case ZT_BONDING_POLICY_ACTIVE_BACKUP:
processActiveBackupTasks(tPtr, now);
break;
case ZT_BONDING_POLICY_BROADCAST:
break;
case ZT_BONDING_POLICY_BALANCE_RR:
case ZT_BONDING_POLICY_BALANCE_XOR:
case ZT_BONDING_POLICY_BALANCE_AWARE:
processBalanceTasks(now);
break;
default:
break;
}
// Check whether or not a path negotiation needs to be performed
if (((now - _lastPathNegotiationCheck) > ZT_PATH_NEGOTIATION_CHECK_INTERVAL) && _allowPathNegotiation) {
_lastPathNegotiationCheck = now;
pathNegotiationCheck(tPtr, now);
}
}
void Bond::applyUserPrefs()
{
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i]) {
continue;
}
SharedPtr<Link> sl = getLink(_paths[i]);
if (sl) {
if (sl->monitorInterval() == 0) { // If no interval was specified for this link, use more generic bond-wide interval
sl->setMonitorInterval(_bondMonitorInterval);
}
RR->bc->setMinReqPathMonitorInterval((sl->monitorInterval() < RR->bc->minReqPathMonitorInterval()) ? sl->monitorInterval() : RR->bc->minReqPathMonitorInterval());
bool bFoundCommonLink = false;
SharedPtr<Link> commonLink =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
for(unsigned int j=0;j<ZT_MAX_PEER_NETWORK_PATHS;++j) {
if (_paths[j] && _paths[j].ptr() != _paths[i].ptr()) {
if (RR->bc->getLinkBySocket(_policyAlias, _paths[j]->localSocket()) == commonLink) {
bFoundCommonLink = true;
}
}
}
_paths[i]->_monitorInterval = sl->monitorInterval();
_paths[i]->_upDelay = sl->upDelay() ? sl->upDelay() : _upDelay;
_paths[i]->_downDelay = sl->downDelay() ? sl->downDelay() : _downDelay;
_paths[i]->_ipvPref = sl->ipvPref();
_paths[i]->_mode = sl->mode();
_paths[i]->_enabled = sl->enabled();
_paths[i]->_onlyPathOnLink = !bFoundCommonLink;
}
}
if (_peer) {
_peer->_shouldCollectPathStatistics = _shouldCollectPathStatistics;
_peer->_bondingPolicy = _bondingPolicy;
}
}
void Bond::curateBond(const int64_t now, bool rebuildBond)
{
char traceMsg[256];
char pathStr[128];
uint8_t tmpNumAliveLinks = 0;
uint8_t tmpNumTotalLinks = 0;
/**
* Update path states
*/
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i]) {
continue;
}
tmpNumTotalLinks++;
if (_paths[i]->alive(now, true)) {
tmpNumAliveLinks++;
}
bool currEligibility = _paths[i]->eligible(now,_ackSendInterval);
if (currEligibility != _paths[i]->_lastEligibilityState) {
_paths[i]->address().toString(pathStr);
char traceMsg[256]; _paths[i]->address().toString(pathStr);
sprintf(traceMsg, "%s (bond) Eligibility of link %s/%s to peer %llx has changed from %d to %d",
OSUtils::humanReadableTimestamp().c_str(), getLink(_paths[i])->ifname().c_str(), pathStr, _peer->_id.address().toInt(), _paths[i]->_lastEligibilityState, currEligibility);
RR->t->bondStateMessage(NULL, traceMsg);
if (currEligibility) {
rebuildBond = true;
}
if (!currEligibility) {
_paths[i]->adjustRefractoryPeriod(now, _defaultPathRefractoryPeriod, !currEligibility);
if (_paths[i]->bonded()) {
char pathStr[128]; _paths[i]->address().toString(pathStr);
sprintf(traceMsg, "%s (bond) Link %s/%s to peer %llx was bonded, reallocation of its flows will occur soon",
OSUtils::humanReadableTimestamp().c_str(), getLink(_paths[i])->ifname().c_str(), pathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
rebuildBond = true;
_paths[i]->_shouldReallocateFlows = _paths[i]->bonded();
_paths[i]->setBonded(false);
} else {
sprintf(traceMsg, "%s (bond) Link %s/%s to peer %llx was not bonded, no allocation consequences",
OSUtils::humanReadableTimestamp().c_str(), getLink(_paths[i])->ifname().c_str(), pathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
if (currEligibility) {
_paths[i]->adjustRefractoryPeriod(now, _defaultPathRefractoryPeriod, false);
}
_paths[i]->_lastEligibilityState = currEligibility;
}
_numAliveLinks = tmpNumAliveLinks;
_numTotalLinks = tmpNumTotalLinks;
/* Determine health status to report to user */
bool tmpHealthStatus = true;
if (_bondingPolicy == ZT_BONDING_POLICY_ACTIVE_BACKUP) {
if (_numAliveLinks < 2) {
// Considered healthy if there is at least one failover link
tmpHealthStatus = false;
}
}
if (_bondingPolicy == ZT_BONDING_POLICY_BROADCAST) {
if (_numAliveLinks < 1) {
// Considerd healthy if we're able to send frames at all
tmpHealthStatus = false;
}
}
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR) {
if (_numAliveLinks < _numTotalLinks) {
// Considerd healthy if all known paths are alive, this should be refined to account for user bond config settings
tmpHealthStatus = false;
}
}
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR) {
if (_numAliveLinks < _numTotalLinks) {
// Considerd healthy if all known paths are alive, this should be refined to account for user bond config settings
tmpHealthStatus = false;
}
}
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
if (_numAliveLinks < _numTotalLinks) {
// Considerd healthy if all known paths are alive, this should be refined to account for user bond config settings
tmpHealthStatus = false;
}
}
if (tmpHealthStatus != _isHealthy) {
std::string healthStatusStr;
if (tmpHealthStatus == true) {
healthStatusStr = "HEALTHY";
} else {
healthStatusStr = "DEGRADED";
}
sprintf(traceMsg, "%s (bond) Bond to peer %llx is in a %s state (%d/%d links)",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), healthStatusStr.c_str(), _numAliveLinks, _numTotalLinks);
RR->t->bondStateMessage(NULL, traceMsg);
}
_isHealthy = tmpHealthStatus;
/**
* Curate the set of paths that are part of the bond proper. Selects a single path
* per logical link according to eligibility and user-specified constraints.
*/
if ((_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR)
|| (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR)
|| (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE)) {
if (!_numBondedPaths) {
rebuildBond = true;
}
// TODO: Optimize
if (rebuildBond) {
int updatedBondedPathCount = 0;
std::map<SharedPtr<Link>,int> linkMap;
for (int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i] && _paths[i]->allowed() && (_paths[i]->eligible(now,_ackSendInterval) || !_numBondedPaths)) {
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
if (!linkMap.count(link)) {
linkMap[link] = i;
}
else {
bool overriden = false;
_paths[i]->address().toString(pathStr);
//fprintf(stderr, " link representative path already exists! (%s %s)\n", getLink(_paths[i])->ifname().c_str(), pathStr);
if (_paths[i]->preferred() && !_paths[linkMap[link]]->preferred()) {
// Override previous choice if preferred
if (_paths[linkMap[link]]->_assignedFlowCount) {
_paths[linkMap[link]]->_deprecated = true;
}
else {
_paths[linkMap[link]]->_deprecated = true;
_paths[linkMap[link]]->setBonded(false);
}
linkMap[link] = i;
overriden = true;
}
if ((_paths[i]->preferred() && _paths[linkMap[link]]->preferred())
|| (!_paths[i]->preferred() && !_paths[linkMap[link]]->preferred())) {
if (_paths[i]->preferenceRank() > _paths[linkMap[link]]->preferenceRank()) {
// Override if higher preference
if (_paths[linkMap[link]]->_assignedFlowCount) {
_paths[linkMap[link]]->_deprecated = true;
}
else {
_paths[linkMap[link]]->_deprecated = true;
_paths[linkMap[link]]->setBonded(false);
}
linkMap[link] = i;
}
}
}
}
}
std::map<SharedPtr<Link>,int>::iterator it = linkMap.begin();
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (!_paths[i]) {
continue;
}
_bondedIdx[i] = ZT_MAX_PEER_NETWORK_PATHS;
if (it != linkMap.end()) {
_bondedIdx[i] = it->second;
_paths[_bondedIdx[i]]->setBonded(true);
++it;
++updatedBondedPathCount;
_paths[_bondedIdx[i]]->address().toString(pathStr);
//fprintf(stderr, "setting i=%d, _bondedIdx[%d]=%d to bonded (%s %s)\n", i, i, _bondedIdx[i], getLink(_paths[_bondedIdx[i]])->ifname().c_str(), pathStr);
}
}
_numBondedPaths = updatedBondedPathCount;
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR) {
// Cause a RR reset since the currently used index might no longer be valid
_rrPacketsSentOnCurrLink = _packetsPerLink;
}
}
}
}
void Bond::estimatePathQuality(const int64_t now)
{
char pathStr[128];
uint32_t totUserSpecifiedLinkSpeed = 0;
if (_numBondedPaths) { // Compute relative user-specified speeds of links
for(unsigned int i=0;i<_numBondedPaths;++i) {
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
if (_paths[i] && _paths[i]->allowed()) {
totUserSpecifiedLinkSpeed += link->speed();
}
}
for(unsigned int i=0;i<_numBondedPaths;++i) {
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
if (_paths[i] && _paths[i]->allowed()) {
link->setRelativeSpeed(round( ((float)link->speed() / (float)totUserSpecifiedLinkSpeed) * 255));
}
}
}
float lat[ZT_MAX_PEER_NETWORK_PATHS];
float pdv[ZT_MAX_PEER_NETWORK_PATHS];
float plr[ZT_MAX_PEER_NETWORK_PATHS];
float per[ZT_MAX_PEER_NETWORK_PATHS];
float maxLAT = 0;
float maxPDV = 0;
float maxPLR = 0;
float maxPER = 0;
float quality[ZT_MAX_PEER_NETWORK_PATHS];
uint8_t alloc[ZT_MAX_PEER_NETWORK_PATHS];
float totQuality = 0.0f;
memset(&lat, 0, sizeof(lat));
memset(&pdv, 0, sizeof(pdv));
memset(&plr, 0, sizeof(plr));
memset(&per, 0, sizeof(per));
memset(&quality, 0, sizeof(quality));
memset(&alloc, 0, sizeof(alloc));
// Compute initial summary statistics
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i] || !_paths[i]->allowed()) {
continue;
}
// Compute/Smooth average of real-world observations
_paths[i]->_latencyMean = _paths[i]->latencySamples.mean();
_paths[i]->_latencyVariance = _paths[i]->latencySamples.stddev();
_paths[i]->_packetErrorRatio = 1.0 - (_paths[i]->packetValiditySamples.count() ? _paths[i]->packetValiditySamples.mean() : 1.0);
if (userHasSpecifiedLinkSpeeds()) {
// Use user-reported metrics
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
if (link) {
_paths[i]->_throughputMean = link->speed();
_paths[i]->_throughputVariance = 0;
}
}
// Drain unacknowledged QoS records
std::map<uint64_t,uint64_t>::iterator it = _paths[i]->qosStatsOut.begin();
uint64_t currentLostRecords = 0;
while (it != _paths[i]->qosStatsOut.end()) {
int qosRecordTimeout = 5000; //_paths[i]->monitorInterval() * ZT_MULTIPATH_QOS_ACK_INTERVAL_MULTIPLIER * 8;
if ((now - it->second) >= qosRecordTimeout) {
// Packet was lost
it = _paths[i]->qosStatsOut.erase(it);
++currentLostRecords;
} else { ++it; }
}
quality[i]=0;
totQuality=0;
// Normalize raw observations according to sane limits and/or user specified values
lat[i] = 1.0 / expf(4*Utils::normalize(_paths[i]->_latencyMean, 0, _maxAcceptableLatency, 0, 1));
pdv[i] = 1.0 / expf(4*Utils::normalize(_paths[i]->_latencyVariance, 0, _maxAcceptablePacketDelayVariance, 0, 1));
plr[i] = 1.0 / expf(4*Utils::normalize(_paths[i]->_packetLossRatio, 0, _maxAcceptablePacketLossRatio, 0, 1));
per[i] = 1.0 / expf(4*Utils::normalize(_paths[i]->_packetErrorRatio, 0, _maxAcceptablePacketErrorRatio, 0, 1));
// Record bond-wide maximums to determine relative values
maxLAT = lat[i] > maxLAT ? lat[i] : maxLAT;
maxPDV = pdv[i] > maxPDV ? pdv[i] : maxPDV;
maxPLR = plr[i] > maxPLR ? plr[i] : maxPLR;
maxPER = per[i] > maxPER ? per[i] : maxPER;
}
// Convert metrics to relative quantities and apply contribution weights
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i] && _paths[i]->bonded()) {
quality[i] += ((maxLAT > 0.0f ? lat[i] / maxLAT : 0.0f) * _qualityWeights[ZT_QOS_LAT_IDX]);
quality[i] += ((maxPDV > 0.0f ? pdv[i] / maxPDV : 0.0f) * _qualityWeights[ZT_QOS_PDV_IDX]);
quality[i] += ((maxPLR > 0.0f ? plr[i] / maxPLR : 0.0f) * _qualityWeights[ZT_QOS_PLR_IDX]);
quality[i] += ((maxPER > 0.0f ? per[i] / maxPER : 0.0f) * _qualityWeights[ZT_QOS_PER_IDX]);
totQuality += quality[i];
}
}
// Normalize to 8-bit allocation values
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i] && _paths[i]->bonded()) {
alloc[i] = std::ceil((quality[i] / totQuality) * (float)255);
_paths[i]->_allocation = alloc[i];
}
}
}
void Bond::processBalanceTasks(const int64_t now)
{
char curPathStr[128];
// TODO: Generalize
int totalAllocation = 0;
for (int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i]) {
continue;
}
if (_paths[i] && _paths[i]->bonded() && _paths[i]->eligible(now,_ackSendInterval)) {
totalAllocation+=_paths[i]->_allocation;
}
}
unsigned char minimumAllocationValue = 0.33 * ((float)totalAllocation / (float)_numBondedPaths);
if (_allowFlowHashing) {
/**
* Clean up and reset flows if necessary
*/
if ((now - _lastFlowExpirationCheck) > ZT_MULTIPATH_FLOW_CHECK_INTERVAL) {
Mutex::Lock _l(_flows_m);
forgetFlowsWhenNecessary(ZT_MULTIPATH_FLOW_EXPIRATION_INTERVAL,false,now);
_lastFlowExpirationCheck = now;
}
if ((now - _lastFlowStatReset) > ZT_FLOW_STATS_RESET_INTERVAL) {
Mutex::Lock _l(_flows_m);
_lastFlowStatReset = now;
std::map<int32_t,SharedPtr<Flow> >::iterator it = _flows.begin();
while (it != _flows.end()) {
it->second->resetByteCounts();
++it;
}
}
/**
* Re-allocate flows from dead paths
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR || _bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
Mutex::Lock _l(_flows_m);
for (int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i]) {
continue;
}
if (!_paths[i]->eligible(now,_ackSendInterval) && _paths[i]->_shouldReallocateFlows) {
char traceMsg[256]; char pathStr[128]; _paths[i]->address().toString(pathStr);
sprintf(traceMsg, "%s (balance-*) Reallocating flows to peer %llx from dead link %s/%s to surviving links",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), getLink(_paths[i])->ifname().c_str(), pathStr);
RR->t->bondStateMessage(NULL, traceMsg);
std::map<int32_t,SharedPtr<Flow> >::iterator flow_it = _flows.begin();
while (flow_it != _flows.end()) {
if (flow_it->second->assignedPath() == _paths[i]) {
if(assignFlowToBondedPath(flow_it->second, now)) {
_paths[i]->_assignedFlowCount--;
}
}
++flow_it;
}
_paths[i]->_shouldReallocateFlows = false;
}
}
}
/**
* Re-allocate flows from under-performing
* NOTE: This could be part of the above block but was kept separate for clarity.
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR || _bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
Mutex::Lock _l(_flows_m);
for (int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (!_paths[i]) {
continue;
}
if (_paths[i] && _paths[i]->bonded() && _paths[i]->eligible(now,_ackSendInterval) && (_paths[i]->_allocation < minimumAllocationValue) && _paths[i]->_assignedFlowCount) {
_paths[i]->address().toString(curPathStr);
char traceMsg[256]; char pathStr[128]; _paths[i]->address().toString(pathStr);
sprintf(traceMsg, "%s (balance-*) Reallocating flows to peer %llx from under-performing link %s/%s\n",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), getLink(_paths[i])->ifname().c_str(), pathStr);
RR->t->bondStateMessage(NULL, traceMsg);
std::map<int32_t,SharedPtr<Flow> >::iterator flow_it = _flows.begin();
while (flow_it != _flows.end()) {
if (flow_it->second->assignedPath() == _paths[i]) {
if(assignFlowToBondedPath(flow_it->second, now)) {
_paths[i]->_assignedFlowCount--;
}
}
++flow_it;
}
_paths[i]->_shouldReallocateFlows = false;
}
}
}
}
/**
* Tasks specific to (Balance Round Robin)
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_RR) {
if (_allowFlowHashing) {
// TODO: Should ideally failover from (idx) to a random link, this is so that (idx+1) isn't overloaded
}
else if (!_allowFlowHashing) {
// Nothing
}
}
/**
* Tasks specific to (Balance XOR)
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_XOR) {
// Nothing specific for XOR
}
/**
* Tasks specific to (Balance Aware)
*/
if (_bondingPolicy == ZT_BONDING_POLICY_BALANCE_AWARE) {
if (_allowFlowHashing) {
Mutex::Lock _l(_flows_m);
if (_flowRebalanceStrategy == ZT_MULTIPATH_FLOW_REBALANCE_STRATEGY_PASSIVE) {
// Do nothing here, this is taken care of in the more general case above.
}
if (_flowRebalanceStrategy == ZT_MULTIPATH_FLOW_REBALANCE_STRATEGY_OPPORTUNISTIC) {
// If the flow is temporarily inactive we should take this opportunity to re-assign the flow if needed.
}
if (_flowRebalanceStrategy == ZT_MULTIPATH_FLOW_REBALANCE_STRATEGY_AGGRESSIVE) {
/**
* Return flows to the original path if it has once again become available
*/
if ((now - _lastFlowRebalance) > ZT_FLOW_REBALANCE_INTERVAL) {
std::map<int32_t,SharedPtr<Flow> >::iterator flow_it = _flows.begin();
while (flow_it != _flows.end()) {
if (flow_it->second->_previouslyAssignedPath && flow_it->second->_previouslyAssignedPath->eligible(now, _ackSendInterval)
&& (flow_it->second->_previouslyAssignedPath->_allocation >= (minimumAllocationValue * 2))) {
//fprintf(stderr, "moving flow back onto its previous path assignment (based on eligibility)\n");
(flow_it->second->_assignedPath->_assignedFlowCount)--;
flow_it->second->assignPath(flow_it->second->_previouslyAssignedPath,now);
(flow_it->second->_previouslyAssignedPath->_assignedFlowCount)++;
}
++flow_it;
}
_lastFlowRebalance = now;
}
/**
* Return flows to the original path if it has once again become (performant)
*/
if ((now - _lastFlowRebalance) > ZT_FLOW_REBALANCE_INTERVAL) {
std::map<int32_t,SharedPtr<Flow> >::iterator flow_it = _flows.begin();
while (flow_it != _flows.end()) {
if (flow_it->second->_previouslyAssignedPath && flow_it->second->_previouslyAssignedPath->eligible(now, _ackSendInterval)
&& (flow_it->second->_previouslyAssignedPath->_allocation >= (minimumAllocationValue * 2))) {
//fprintf(stderr, "moving flow back onto its previous path assignment (based on performance)\n");
(flow_it->second->_assignedPath->_assignedFlowCount)--;
flow_it->second->assignPath(flow_it->second->_previouslyAssignedPath,now);
(flow_it->second->_previouslyAssignedPath->_assignedFlowCount)++;
}
++flow_it;
}
_lastFlowRebalance = now;
}
}
}
else if (!_allowFlowHashing) {
// Nothing
}
}
}
void Bond::dequeueNextActiveBackupPath(const uint64_t now)
{
if (_abFailoverQueue.empty()) {
return;
}
_abPath = _abFailoverQueue.front();
_abFailoverQueue.pop_front();
_lastActiveBackupPathChange = now;
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (_paths[i]) {
_paths[i]->resetPacketCounts();
}
}
}
void Bond::processActiveBackupTasks(void *tPtr, const int64_t now)
{
char traceMsg[256];
char pathStr[128];
char prevPathStr[128];
char curPathStr[128];
SharedPtr<Path> prevActiveBackupPath = _abPath;
SharedPtr<Path> nonPreferredPath;
bool bFoundPrimaryLink = false;
/**
* Generate periodic statuc report
*/
if ((now - _lastBondStatusLog) > ZT_MULTIPATH_BOND_STATUS_INTERVAL) {
_lastBondStatusLog = now;
if (_abPath) {
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Active link to peer %llx is %s/%s, failover queue size is %zu",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), getLink(_abPath)->ifname().c_str(), curPathStr, _abFailoverQueue.size());
RR->t->bondStateMessage(NULL, traceMsg);
} else {
sprintf(traceMsg, "%s (active-backup) No active link to peer %llx",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
if (_abFailoverQueue.empty()) {
sprintf(traceMsg, "%s (active-backup) Failover queue is empty, bond to peer %llx is NOT currently fault-tolerant",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
/**
* Select initial "active" active-backup link
*/
if (!_abPath) {
/**
* [Automatic mode]
* The user has not explicitly specified links or their failover schedule,
* the bonding policy will now select the first eligible path and set it as
* its active backup path, if a substantially better path is detected the bonding
* policy will assign it as the new active backup path. If the path fails it will
* simply find the next eligible path.
*/
if (!userHasSpecifiedLinks()) {
sprintf(traceMsg, "%s (active-backup) No links to peer %llx specified. Searching...",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt()); RR->t->bondStateMessage(NULL, traceMsg);
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (_paths[i] && _paths[i]->eligible(now,_ackSendInterval)) {
_paths[i]->address().toString(curPathStr);
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
if (link) {
sprintf(traceMsg, "%s (active-backup) Found eligible link %s/%s to peer %llx",
OSUtils::humanReadableTimestamp().c_str(), getLink(_paths[i])->ifname().c_str(), curPathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
_abPath = _paths[i];
break;
}
}
}
/**
* [Manual mode]
* The user has specified links or failover rules that the bonding policy should adhere to.
*/
else if (userHasSpecifiedLinks()) {
if (userHasSpecifiedPrimaryLink()) {
//sprintf(traceMsg, "%s (active-backup) Checking local.conf for user-specified primary link\n", OSUtils::humanReadableTimestamp().c_str());
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (!_paths[i]) {
continue;
}
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
if (_paths[i]->eligible(now,_ackSendInterval) && link->primary()) {
if (!_paths[i]->preferred()) {
_paths[i]->address().toString(curPathStr);
// Found path on primary link, take note in case we don't find a preferred path
nonPreferredPath = _paths[i];
bFoundPrimaryLink = true;
}
if (_paths[i]->preferred()) {
_abPath = _paths[i];
_abPath->address().toString(curPathStr);
SharedPtr<Link> link = RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
bFoundPrimaryLink = true;
break; // Found preferred path %s on primary link
}
}
}
if (_abPath) {
_abPath->address().toString(curPathStr);
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _abPath->localSocket());
if (link) {
sprintf(traceMsg, "%s (active-backup) Found preferred primary link %s/%s to peer %llx",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
else {
if (bFoundPrimaryLink && nonPreferredPath) {
sprintf(traceMsg, "%s (active-backup) Found non-preferred primary link to peer %llx",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
_abPath = nonPreferredPath;
}
}
if (!_abPath) {
sprintf(traceMsg, "%s (active-backup) Designated primary link to peer %llx is not yet ready",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
// TODO: Should wait for some time (failover interval?) and then swtich to spare link
}
}
else if (!userHasSpecifiedPrimaryLink()) {
int _abIdx = ZT_MAX_PEER_NETWORK_PATHS;
sprintf(traceMsg, "%s (active-backup) User did not specify a primary link to peer %llx, selecting first available link",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (_paths[i] && _paths[i]->eligible(now,_ackSendInterval)) {
_abIdx = i;
break;
}
}
if (_abIdx == ZT_MAX_PEER_NETWORK_PATHS) {
// Unable to find a candidate next-best, no change
}
else {
_abPath = _paths[_abIdx];
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _abPath->localSocket());
if (link) {
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Selected non-primary link %s/%s to peer %llx",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
}
}
/**
* Update and maintain the active-backup failover queue
*/
if (_abPath) {
// Don't worry about the failover queue until we have an active link
// Remove ineligible paths from the failover link queue
for (std::list<SharedPtr<Path> >::iterator it(_abFailoverQueue.begin()); it!=_abFailoverQueue.end();) {
if ((*it) && !(*it)->eligible(now,_ackSendInterval)) {
(*it)->address().toString(curPathStr);
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, (*it)->localSocket());
it = _abFailoverQueue.erase(it);
if (link) {
sprintf(traceMsg, "%s (active-backup) Link %s/%s to peer %llx is now ineligible, removing from failover queue, there are %zu links in the queue",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt(), _abFailoverQueue.size());
RR->t->bondStateMessage(NULL, traceMsg);
}
} else {
++it;
}
}
/**
* Failover instructions were provided by user, build queue according those as well as IPv
* preference, disregarding performance.
*/
if (userHasSpecifiedFailoverInstructions()) {
/**
* Clear failover scores
*/
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (_paths[i]) {
_paths[i]->_failoverScore = 0;
}
}
// Follow user-specified failover instructions
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (!_paths[i] || !_paths[i]->allowed() || !_paths[i]->eligible(now,_ackSendInterval)) {
continue;
}
SharedPtr<Link> link =RR->bc->getLinkBySocket(_policyAlias, _paths[i]->localSocket());
_paths[i]->address().toString(pathStr);
int failoverScoreHandicap = _paths[i]->_failoverScore;
if (_paths[i]->preferred()) {
failoverScoreHandicap += ZT_MULTIPATH_FAILOVER_HANDICAP_PREFERRED;
}
if (link->primary()) {
// If using "optimize" primary reselect mode, ignore user link designations
failoverScoreHandicap += ZT_MULTIPATH_FAILOVER_HANDICAP_PRIMARY;
}
if (!_paths[i]->_failoverScore) {
// If we didn't inherit a failover score from a "parent" that wants to use this path as a failover
int newHandicap = failoverScoreHandicap ? failoverScoreHandicap : _paths[i]->_allocation;
_paths[i]->_failoverScore = newHandicap;
}
SharedPtr<Link> failoverLink;
if (link->failoverToLink().length()) {
failoverLink = RR->bc->getLinkByName(_policyAlias, link->failoverToLink());
}
if (failoverLink) {
for (int j=0; j<ZT_MAX_PEER_NETWORK_PATHS; j++) {
if (_paths[j] && getLink(_paths[j]) == failoverLink.ptr()) {
_paths[j]->address().toString(pathStr);
int inheritedHandicap = failoverScoreHandicap - 10;
int newHandicap = _paths[j]->_failoverScore > inheritedHandicap ? _paths[j]->_failoverScore : inheritedHandicap;
if (!_paths[j]->preferred()) {
newHandicap--;
}
_paths[j]->_failoverScore = newHandicap;
}
}
}
if (_paths[i].ptr() != _abPath.ptr()) {
bool bFoundPathInQueue = false;
for (std::list<SharedPtr<Path> >::iterator it(_abFailoverQueue.begin()); it!=_abFailoverQueue.end();++it) {
if (_paths[i].ptr() == (*it).ptr()) {
bFoundPathInQueue = true;
}
}
if (!bFoundPathInQueue) {
_abFailoverQueue.push_front(_paths[i]);
_paths[i]->address().toString(curPathStr); sprintf(traceMsg, "%s (active-backup) Added link %s/%s to peer %llx to failover queue, there are %zu links in the queue",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt(), _abFailoverQueue.size());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
}
/**
* No failover instructions provided by user, build queue according to performance
* and IPv preference.
*/
else if (!userHasSpecifiedFailoverInstructions()) {
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; ++i) {
if (!_paths[i]
|| !_paths[i]->allowed()
|| !_paths[i]->eligible(now,_ackSendInterval)) {
continue;
}
int failoverScoreHandicap = 0;
if (_paths[i]->preferred()) {
failoverScoreHandicap = ZT_MULTIPATH_FAILOVER_HANDICAP_PREFERRED;
}
bool includeRefractoryPeriod = true;
if (!_paths[i]->eligible(now,includeRefractoryPeriod)) {
failoverScoreHandicap = -10000;
}
if (getLink(_paths[i])->primary() && _abLinkSelectMethod != ZT_MULTIPATH_RESELECTION_POLICY_OPTIMIZE) {
// If using "optimize" primary reselect mode, ignore user link designations
failoverScoreHandicap = ZT_MULTIPATH_FAILOVER_HANDICAP_PRIMARY;
}
if (_paths[i].ptr() == negotiatedPath.ptr()) {
_paths[i]->_negotiated = true;
failoverScoreHandicap = ZT_MULTIPATH_FAILOVER_HANDICAP_NEGOTIATED;
} else {
_paths[i]->_negotiated = false;
}
_paths[i]->_failoverScore = _paths[i]->_allocation + failoverScoreHandicap;
if (_paths[i].ptr() != _abPath.ptr()) {
bool bFoundPathInQueue = false;
for (std::list<SharedPtr<Path> >::iterator it(_abFailoverQueue.begin()); it!=_abFailoverQueue.end();++it) {
if (_paths[i].ptr() == (*it).ptr()) {
bFoundPathInQueue = true;
}
}
if (!bFoundPathInQueue) {
_abFailoverQueue.push_front(_paths[i]);
_paths[i]->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Added link %s/%s to peer %llx, there are %zu links in the queue",
OSUtils::humanReadableTimestamp().c_str(), getLink(_paths[i])->ifname().c_str(), curPathStr, _peer->_id.address().toInt(), _abFailoverQueue.size());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
}
_abFailoverQueue.sort(PathQualityComparator());
}
/**
* Short-circuit if we have no queued paths
*/
if (_abFailoverQueue.empty()) {
return;
}
/**
* Fulfill primary reselect obligations
*/
if (_abPath && !_abPath->eligible(now,_ackSendInterval)) { // Implicit ZT_MULTIPATH_RESELECTION_POLICY_FAILURE
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Link %s/%s to peer %llx has failed. Selecting new link from failover queue, there are %zu links in the queue",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt(), _abFailoverQueue.size());
RR->t->bondStateMessage(NULL, traceMsg);
if (!_abFailoverQueue.empty()) {
dequeueNextActiveBackupPath(now);
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Active link to peer %llx has been switched to %s/%s",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt(), getLink(_abPath)->ifname().c_str(), curPathStr);
RR->t->bondStateMessage(NULL, traceMsg);
} else {
sprintf(traceMsg, "%s (active-backup) Failover queue is empty. No links to peer %llx to choose from",
OSUtils::humanReadableTimestamp().c_str(), _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
/**
* Detect change to prevent flopping during later optimization step.
*/
if (prevActiveBackupPath != _abPath) {
_lastActiveBackupPathChange = now;
}
if (_abLinkSelectMethod == ZT_MULTIPATH_RESELECTION_POLICY_ALWAYS) {
if (_abPath && !getLink(_abPath)->primary()
&& getLink(_abFailoverQueue.front())->primary()) {
dequeueNextActiveBackupPath(now);
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Switching back to available primary link %s/%s to peer %llx [linkSelectionMethod = always]",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
if (_abLinkSelectMethod == ZT_MULTIPATH_RESELECTION_POLICY_BETTER) {
if (_abPath && !getLink(_abPath)->primary()) {
// Active backup has switched to "better" primary link according to re-select policy.
if (getLink(_abFailoverQueue.front())->primary()
&& (_abFailoverQueue.front()->_failoverScore > _abPath->_failoverScore)) {
dequeueNextActiveBackupPath(now);
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Switching back to user-defined primary link %s/%s to peer %llx [linkSelectionMethod = better]",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
if (_abLinkSelectMethod == ZT_MULTIPATH_RESELECTION_POLICY_OPTIMIZE && !_abFailoverQueue.empty()) {
/**
* Implement link negotiation that was previously-decided
*/
if (_abFailoverQueue.front()->_negotiated) {
dequeueNextActiveBackupPath(now);
_abPath->address().toString(prevPathStr);
_lastPathNegotiationCheck = now;
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Switching negotiated link %s/%s to peer %llx [linkSelectionMethod = optimize]",
OSUtils::humanReadableTimestamp().c_str(), getLink(_abPath)->ifname().c_str(), curPathStr, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
else {
// Try to find a better path and automatically switch to it -- not too often, though.
if ((now - _lastActiveBackupPathChange) > ZT_MULTIPATH_MIN_ACTIVE_BACKUP_AUTOFLOP_INTERVAL) {
if (!_abFailoverQueue.empty()) {
int newFScore = _abFailoverQueue.front()->_failoverScore;
int prevFScore = _abPath->_failoverScore;
// Establish a minimum switch threshold to prevent flapping
int failoverScoreDifference = _abFailoverQueue.front()->_failoverScore - _abPath->_failoverScore;
int thresholdQuantity = (ZT_MULTIPATH_ACTIVE_BACKUP_OPTIMIZE_MIN_THRESHOLD * (float)_abPath->_allocation);
if ((failoverScoreDifference > 0) && (failoverScoreDifference > thresholdQuantity)) {
SharedPtr<Path> oldPath = _abPath;
_abPath->address().toString(prevPathStr);
dequeueNextActiveBackupPath(now);
_abPath->address().toString(curPathStr);
sprintf(traceMsg, "%s (active-backup) Switching from %s/%s (fscore=%d) to better link %s/%s (fscore=%d) for peer %llx [linkSelectionMethod = optimize]",
OSUtils::humanReadableTimestamp().c_str(), getLink(oldPath)->ifname().c_str(), prevPathStr, prevFScore, getLink(_abPath)->ifname().c_str(), curPathStr, newFScore, _peer->_id.address().toInt());
RR->t->bondStateMessage(NULL, traceMsg);
}
}
}
}
}
}
void Bond::setReasonableDefaults(int policy, SharedPtr<Bond> templateBond, bool useTemplate)
{
// If invalid bonding policy, try default
int _defaultBondingPolicy = BondController::defaultBondingPolicy();
if (policy <= ZT_BONDING_POLICY_NONE || policy > ZT_BONDING_POLICY_BALANCE_AWARE) {
// If no default set, use NONE (effectively disabling this bond)
if (_defaultBondingPolicy < ZT_BONDING_POLICY_NONE || _defaultBondingPolicy > ZT_BONDING_POLICY_BALANCE_AWARE) {
_bondingPolicy= ZT_BONDING_POLICY_NONE;
}
_bondingPolicy= _defaultBondingPolicy;
} else {
_bondingPolicy= policy;
}
_freeRandomByte = 0;
_userHasSpecifiedPrimaryLink = false;
_userHasSpecifiedFailoverInstructions = false;
_isHealthy = false;
_numAliveLinks = 0;
_numTotalLinks = 0;
_downDelay = 0;
_upDelay = 0;
_allowFlowHashing=false;
_bondMonitorInterval=0;
_shouldCollectPathStatistics=false;
// Path negotiation
_allowPathNegotiation=false;
_pathNegotiationCutoffCount=0;
_localUtility=0;
_numBondedPaths=0;
_rrPacketsSentOnCurrLink=0;
_rrIdx=0;
_totalBondUnderload = 0;
_maxAcceptableLatency = 100;
_maxAcceptablePacketDelayVariance = 50;
_maxAcceptablePacketLossRatio = 0.10;
_maxAcceptablePacketErrorRatio = 0.10;
_userHasSpecifiedLinkSpeeds=0;
/* ZT_MULTIPATH_FLOW_REBALANCE_STRATEGY_PASSIVE is the most conservative strategy and is
least likely to cause unexpected behavior */
_flowRebalanceStrategy = ZT_MULTIPATH_FLOW_REBALANCE_STRATEGY_AGGRESSIVE;
/**
* Paths are actively monitored to provide a real-time quality/preference-ordered rapid failover queue.
*/
switch (policy) {
case ZT_BONDING_POLICY_ACTIVE_BACKUP:
_failoverInterval = 500;
_abLinkSelectMethod = ZT_MULTIPATH_RESELECTION_POLICY_OPTIMIZE;
_linkMonitorStrategy = ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_DYNAMIC;
_qualityWeights[ZT_QOS_LAT_IDX] = 0.2f;
_qualityWeights[ZT_QOS_LTM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_PDV_IDX] = 0.2f;
_qualityWeights[ZT_QOS_PLR_IDX] = 0.2f;
_qualityWeights[ZT_QOS_PER_IDX] = 0.2f;
_qualityWeights[ZT_QOS_THR_IDX] = 0.2f;
_qualityWeights[ZT_QOS_THM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_THV_IDX] = 0.0f;
_qualityWeights[ZT_QOS_SCP_IDX] = 0.0f;
break;
/**
* All seemingly-alive paths are used. Paths are not actively monitored.
*/
case ZT_BONDING_POLICY_BROADCAST:
_downDelay = 30000;
_upDelay = 0;
break;
/**
* Paths are monitored to determine when/if one needs to be added or removed from the rotation
*/
case ZT_BONDING_POLICY_BALANCE_RR:
_failoverInterval = 3000;
_allowFlowHashing = false;
_packetsPerLink = 1024;
_linkMonitorStrategy = ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_DYNAMIC;
_qualityWeights[ZT_QOS_LAT_IDX] = 0.4f;
_qualityWeights[ZT_QOS_LTM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_PDV_IDX] = 0.2f;
_qualityWeights[ZT_QOS_PLR_IDX] = 0.1f;
_qualityWeights[ZT_QOS_PER_IDX] = 0.1f;
_qualityWeights[ZT_QOS_THR_IDX] = 0.1f;
_qualityWeights[ZT_QOS_THM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_THV_IDX] = 0.0f;
_qualityWeights[ZT_QOS_SCP_IDX] = 0.0f;
break;
/**
* Path monitoring is used to determine the capacity of each
* path and where to place the next flow.
*/
case ZT_BONDING_POLICY_BALANCE_XOR:
_failoverInterval = 3000;
_upDelay = _bondMonitorInterval * 2;
_allowFlowHashing = true;
_linkMonitorStrategy = ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_DYNAMIC;
_qualityWeights[ZT_QOS_LAT_IDX] = 0.4f;
_qualityWeights[ZT_QOS_LTM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_PDV_IDX] = 0.2f;
_qualityWeights[ZT_QOS_PLR_IDX] = 0.1f;
_qualityWeights[ZT_QOS_PER_IDX] = 0.1f;
_qualityWeights[ZT_QOS_THR_IDX] = 0.1f;
_qualityWeights[ZT_QOS_THM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_THV_IDX] = 0.0f;
_qualityWeights[ZT_QOS_SCP_IDX] = 0.0f;
break;
/**
* Path monitoring is used to determine the capacity of each
* path and where to place the next flow. Additionally, re-shuffling
* of flows may take place.
*/
case ZT_BONDING_POLICY_BALANCE_AWARE:
_failoverInterval = 3000;
_allowFlowHashing = true;
_linkMonitorStrategy = ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_DYNAMIC;
_qualityWeights[ZT_QOS_LAT_IDX] = 0.4f;
_qualityWeights[ZT_QOS_LTM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_PDV_IDX] = 0.4f;
_qualityWeights[ZT_QOS_PLR_IDX] = 0.2f;
_qualityWeights[ZT_QOS_PER_IDX] = 0.0f;
_qualityWeights[ZT_QOS_THR_IDX] = 0.0f;
_qualityWeights[ZT_QOS_THM_IDX] = 0.0f;
_qualityWeights[ZT_QOS_THV_IDX] = 0.0f;
_qualityWeights[ZT_QOS_SCP_IDX] = 0.0f;
break;
default:
break;
}
/* If a user has specified custom parameters for this bonding policy, overlay
them onto the defaults that were previously set */
if (useTemplate) {
_policyAlias = templateBond->_policyAlias;
_failoverInterval = templateBond->_failoverInterval;
_downDelay = templateBond->_downDelay;
_upDelay = templateBond->_upDelay;
if (templateBond->_linkMonitorStrategy == ZT_MULTIPATH_SLAVE_MONITOR_STRATEGY_PASSIVE
&& templateBond->_failoverInterval != 0) {
//fprintf(stderr, "warning: passive path monitoring was specified, this will prevent failovers from happening in a timely manner.\n");
}
_abLinkSelectMethod = templateBond->_abLinkSelectMethod;
memcpy(_qualityWeights, templateBond->_qualityWeights, ZT_QOS_WEIGHT_SIZE * sizeof(float));
}
/* Set timer geometries */
_bondMonitorInterval = _failoverInterval / 3;
BondController::setMinReqPathMonitorInterval(_bondMonitorInterval);
_ackSendInterval = _failoverInterval;
_qualityEstimationInterval = _failoverInterval * 2;
_dynamicPathMonitorInterval = 0;
_ackCutoffCount = 0;
_qosSendInterval = _bondMonitorInterval * 4;
_qosCutoffCount = 0;
throughputMeasurementInterval = _ackSendInterval * 2;
_defaultPathRefractoryPeriod = 8000;
}
void Bond::setUserQualityWeights(float weights[], int len)
{
if (len == ZT_QOS_WEIGHT_SIZE) {
float weightTotal = 0.0;
for (unsigned int i=0; i<ZT_QOS_WEIGHT_SIZE; ++i) {
weightTotal += weights[i];
}
if (weightTotal > 0.99 && weightTotal < 1.01) {
memcpy(_qualityWeights, weights, len * sizeof(float));
}
}
}
bool Bond::relevant() {
return false;
}
SharedPtr<Link> Bond::getLink(const SharedPtr<Path>& path)
{
return RR->bc->getLinkBySocket(_policyAlias, path->localSocket());
}
void Bond::dumpInfo(const int64_t now)
{
// Omitted
}
} // namespace ZeroTier