diff options
Diffstat (limited to 'hicn-light/src/hicn/strategies/lowLatency.c')
-rw-r--r-- | hicn-light/src/hicn/strategies/lowLatency.c | 851 |
1 files changed, 0 insertions, 851 deletions
diff --git a/hicn-light/src/hicn/strategies/lowLatency.c b/hicn-light/src/hicn/strategies/lowLatency.c deleted file mode 100644 index 61bffe243..000000000 --- a/hicn-light/src/hicn/strategies/lowLatency.c +++ /dev/null @@ -1,851 +0,0 @@ -/* - * Copyright (c) 2017-2019 Cisco and/or its affiliates. - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at: - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#include <hicn/hicn-light/config.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <time.h> -#include <math.h> - -#include <parc/assert/parc_Assert.h> - -#include <parc/algol/parc_HashMap.h> -#include <parc/algol/parc_Memory.h> -#include <parc/algol/parc_Object.h> -#include <parc/algol/parc_Unsigned.h> - -#include <hicn/core/messageHandler.h> - -#include <hicn/strategies/lowLatency.h> -#include <hicn/strategies/nexthopStateLowLatency.h> - -const unsigned STABILITY_FACTOR = 15; -const unsigned MAX_SWITCH_TRY = 10; -const unsigned MAX_LATENCY_DIFF = 10; -const unsigned MAX_TOLLERATED_LATENCY_DIFF = 15; -const unsigned MAX_ROUNDS_MP_WITHOUT_CHECK = 2; -const unsigned MAX_ROUNDS_AVOIDING_MULTIPATH = 40; //about 20 sec -const unsigned MAX_ROUNDS_WITH_ERROR = 4; -const unsigned PROBE_LIFETIME = 500; //ms - -static void _strategyLowLatency_ReceiveObject(StrategyImpl *strategy, - const NumberSet *egressId, - const Message *objectMessage, - Ticks pitEntryCreation, - Ticks objReception); -static void _strategyLowLatency_OnTimeout(StrategyImpl *strategy, - const NumberSet *egressId); -static NumberSet *_strategyLowLatency_LookupNexthop( - StrategyImpl *strategy, -#ifdef WITH_POLICY - NumberSet * nexthops, -#endif /* WITH_POLICY */ - const Message *interestMessage); -#ifndef WITH_POLICY -static NumberSet *_strategyLowLatency_ReturnNexthops(StrategyImpl *strategy); -static unsigned _strategyLowLatency_CountNexthops(StrategyImpl *strategy); -#endif /* ! WITH_POLICY */ -static void _strategyLowLatency_AddNexthop(StrategyImpl *strategy, - unsigned connectionId); -static void _strategyLowLatency_RemoveNexthop(StrategyImpl *strategy, - unsigned connectionId); -static void _strategyLowLatency_ImplDestroy(StrategyImpl **strategyPtr); -static strategy_type _strategyLowLatency_GetStrategy(StrategyImpl *strategy); - -static StrategyImpl _template = { - .context = NULL, - .receiveObject = &_strategyLowLatency_ReceiveObject, - .onTimeout = &_strategyLowLatency_OnTimeout, - .lookupNexthop = &_strategyLowLatency_LookupNexthop, -#ifndef WITH_POLICY - .returnNexthops = &_strategyLowLatency_ReturnNexthops, - .countNexthops = &_strategyLowLatency_CountNexthops, -#endif /* ! WITH_POLICY */ - .addNexthop = &_strategyLowLatency_AddNexthop, - .removeNexthop = &_strategyLowLatency_RemoveNexthop, - .destroy = &_strategyLowLatency_ImplDestroy, - .getStrategy = &_strategyLowLatency_GetStrategy, -}; - -struct strategy_low_latency; -typedef struct strategy_low_latency StrategyLowLatency; - -struct strategy_low_latency { - // hash map from connectionId to StrategyNexthopStateLL - PARCHashMap *strategy_state; - //hash map from sequence number to ticks (sent time) - PARCHashMap *pending_probes_ticks; - //hash map from sequence number to face id - PARCHashMap *pending_probes_faces; - const Forwarder * forwarder; - PARCEventTimer *sendProbes; - PARCEventTimer *computeBestFace; - uint8_t * probe; - hicn_name_t * name; - StrategyNexthopStateLL * bestFaces[2]; - unsigned round; - unsigned rounds_in_multipath; - unsigned rounds_with_error; - unsigned rounds_avoiding_multipath; - bool use2paths; - bool avoid_multipath; - unsigned related_prefixes_len; - Name **related_prefixes; -#ifndef WITH_POLICY - NumberSet *nexthops; -#endif /* ! WITH_POLICY */ -}; - -static void strategyLowLatency_SendProbesCB(int fd, PARCEventType which_event, - void *data){ - parcAssertTrue(which_event & PARCEventType_Timeout, - "Event incorrect, expecting %X set, got %X", - PARCEventType_Timeout, which_event); - - StrategyLowLatency *ll = (StrategyLowLatency *) data; - - //delete old pending probes - if(parcHashMap_Size(ll->pending_probes_ticks) != 0){ - Ticks now = forwarder_GetTicks(ll->forwarder); - PARCIterator *iterator = parcHashMap_CreateKeyIterator(ll->pending_probes_ticks); - NumberSet *to_remove = numberSet_Create(); - while(parcIterator_HasNext(iterator)) { - PARCUnsigned *parc_seq = (PARCUnsigned *) parcIterator_Next(iterator); - PARCUnsigned *parc_time = (PARCUnsigned *) parcHashMap_Get(ll->pending_probes_ticks, parc_seq); - Ticks sent_time = parcUnsigned_GetUnsigned(parc_time); - if((now - sent_time) > PROBE_LIFETIME){ - //probes to delete - numberSet_Add(to_remove, parcUnsigned_GetUnsigned(parc_seq)); - } - } - parcIterator_Release(&iterator); - - for(int i = 0; i < numberSet_Length(to_remove); i++){ - PARCUnsigned *prob_seq = parcUnsigned_Create(numberSet_GetItem(to_remove,i)); - PARCUnsigned *cid = (PARCUnsigned *) parcHashMap_Get(ll->pending_probes_faces, prob_seq); - StrategyNexthopStateLL *state = - (StrategyNexthopStateLL *) parcHashMap_Get(ll->strategy_state, cid); - strategyNexthopStateLL_LostProbe(state); - parcHashMap_Remove(ll->pending_probes_ticks, prob_seq); - parcHashMap_Remove(ll->pending_probes_faces, prob_seq); - parcUnsigned_Release(&prob_seq); - } - numberSet_Release(&to_remove); - } - - ConnectionTable * ct = forwarder_GetConnectionTable(ll->forwarder); - - PARCIterator *iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - while(parcIterator_HasNext(iterator)){ - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - Connection *conn = - (Connection *)connectionTable_FindById(ct, - parcUnsigned_GetUnsigned(cid)); - if(!conn) - continue; - - StrategyNexthopStateLL *state = - (StrategyNexthopStateLL *) parcHashMap_Get(ll->strategy_state, cid); - - //probe only usable paths - if(!strategyNexthopStateLL_IsAllowed(state)) - continue; - - uint32_t seq = rand(); - messageHandler_SetProbeName(ll->probe, HF_INET6_TCP, - ll->name, seq); - connection_Probe(conn, ll->probe); - - PARCUnsigned *parc_seq = parcUnsigned_Create(seq); - Ticks now = forwarder_GetTicks(ll->forwarder); - PARCUnsigned *parc_time = parcUnsigned_Create((unsigned int)now); - parcHashMap_Put(ll->pending_probes_ticks, parc_seq, parc_time); - parcHashMap_Put(ll->pending_probes_faces, parc_seq, cid); - strategyNexthopStateLL_SentProbe(state); - parcUnsigned_Release(&parc_seq); - parcUnsigned_Release(&parc_time); - } - parcIterator_Release(&iterator); - - struct timeval timeout = {0,50000}; - parcEventTimer_Start(ll->sendProbes, &timeout); -} - -static void strategyLowLatency_SendMapmeUpdate(StrategyLowLatency *ll, - const NumberSet * nexthops){ - MapMe * mapme = forwarder_getMapmeInstance(ll->forwarder); - FIB * fib = forwarder_getFib((Forwarder*) ll->forwarder); - if(fib != NULL){ - for(unsigned i = 0; i < ll->related_prefixes_len; i++){ - FibEntry *fibEntry = fib_MatchName(fib, ll->related_prefixes[i]); - if(fibEntry != NULL){ - mapme_maybe_send_updates(mapme, fibEntry, nexthops); - } - } - } -} - -static void strategyLowLatency_SelectBestFaces(StrategyLowLatency *ll, - bool new_round){ - - StrategyNexthopStateLL * old_faces[2]; - old_faces[0] = ll->bestFaces[0]; - old_faces[1] = ll->bestFaces[1]; - - if(new_round){ - ll->round++; - } - - if(parcHashMap_Size(ll->strategy_state) == 0){ - ll->bestFaces[0] = NULL; - ll->bestFaces[1] = NULL; - ll->use2paths = false; - goto NEW_ROUND; - } - - if(ll->use2paths && ll->bestFaces[0] != NULL && ll->bestFaces[1] != NULL){ - //multipath case - - if(!strategyNexthopStateLL_IsLossy(ll->bestFaces[0]) - && !strategyNexthopStateLL_IsLossy(ll->bestFaces[1]) - && strategyNexthopStateLL_IsAllowed(ll->bestFaces[0]) - && strategyNexthopStateLL_IsAllowed(ll->bestFaces[1])){ - - if(ll->rounds_in_multipath < MAX_ROUNDS_MP_WITHOUT_CHECK){ - //we are at the first rounds of the multipath let's wait a bit - //(MAX_ROUNDS_MP_WITHOUT_CHECK) to make the queuing converge - ll->rounds_in_multipath++; - goto NEW_ROUND; - } - - //we need to decide if we want ot keep using two paths or not - ll->rounds_in_multipath++; - double rtt0 = strategyNexthopStateLL_GetRTTLive(ll->bestFaces[0]); - double rtt1 = strategyNexthopStateLL_GetRTTLive(ll->bestFaces[1]); - double diff = fabs(rtt0 - rtt1); - - if(diff < MAX_LATENCY_DIFF){ - //everything is working, keep using the two paths - ll->rounds_with_error = 0; - goto NEW_ROUND; - } - - //check for how many rounds we had problems - if(ll->rounds_with_error < MAX_ROUNDS_WITH_ERROR && - diff < MAX_TOLLERATED_LATENCY_DIFF){ - //we can tollerate few round with errors - ll->rounds_with_error++; - goto NEW_ROUND; - } - - //prevent the usage of multiple paths - ll->rounds_with_error = 0; - ll->avoid_multipath = true; - ll->rounds_avoiding_multipath = 0; - } //else - //at least one of the two path is lossy - //or it is not allowed by the policies. - //search for a better possibility - } - - ll->bestFaces[0] = NULL; - ll->bestFaces[1] = NULL; - - //check if there is at least one non lossy connection - PARCIterator *iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - bool check_losses = true; - bool found_good_face = false; - while(parcIterator_HasNext(iterator) && !found_good_face){ - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - const StrategyNexthopStateLL *state = parcHashMap_Get(ll->strategy_state, cid); - if(!strategyNexthopStateLL_IsLossy(state) && - strategyNexthopStateLL_IsAllowed(state)){ - found_good_face = true; - } - } - parcIterator_Release(&iterator); - if(!found_good_face){ - // all the available faces are lossy, so we take into account only - // the latency computed with the probes - check_losses = false; - } - - if(ll->bestFaces[0] == NULL){ - //try to take a random face - PARCIterator *iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - bool face_found = false; - while(parcIterator_HasNext(iterator) && !face_found) { - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - StrategyNexthopStateLL *state = (StrategyNexthopStateLL *) - parcHashMap_Get(ll->strategy_state, cid); - - if((check_losses && strategyNexthopStateLL_IsLossy(state)) || - !strategyNexthopStateLL_IsAllowed(state)){ - //skip the face - continue; - } - - ll->bestFaces[0] = state; - face_found = true; - } - parcIterator_Release(&iterator); - } - - if(ll->bestFaces[0] == NULL){ - //no usable face exists - ll->bestFaces[0] = NULL; - ll->bestFaces[1] = NULL; - ll->use2paths = false; - goto NEW_ROUND; - } - - double bestRtt = strategyNexthopStateLL_GetRTTLive(ll->bestFaces[0]); - - if(ll->avoid_multipath) - ll->rounds_avoiding_multipath++; - - if(ll->rounds_avoiding_multipath > MAX_ROUNDS_AVOIDING_MULTIPATH){ - ll->avoid_multipath = false; - ll->rounds_avoiding_multipath = 0; - } - - iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - while (parcIterator_HasNext(iterator)) { - - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - StrategyNexthopStateLL *state = (StrategyNexthopStateLL *) - parcHashMap_Get(ll->strategy_state, cid); - double rtt = strategyNexthopStateLL_GetRTTLive(state); - - if((check_losses && strategyNexthopStateLL_IsLossy(state)) || - !strategyNexthopStateLL_IsAllowed(state)){ - //skip the face - continue; - } - - if(rtt + STABILITY_FACTOR < bestRtt){ - //maybe we found a better face - double rttInUse = strategyNexthopStateLL_GetRTTInUse(state); - unsigned try = strategyNexthopStateLL_GetTryToSwitch(state); - - //we check the rtt in use to check if the new face that we found - //gets congested when we use it to send the traffic - if(rttInUse < bestRtt || try > MAX_SWITCH_TRY){ - //we have a new best face! - strategyNexthopStateLL_ResetTryToSwitch((StrategyNexthopStateLL*) state); - bestRtt = rtt; - if(ll->bestFaces[0] != NULL) - strategyNexthopStateLL_SetUnusedFace(ll->bestFaces[0]); - ll->bestFaces[0] = (StrategyNexthopStateLL*) state; - }else{ - //in this case we should switch but we wait MAX_SWITCH_TRY - //before switch to avoid ossillations between different paths - strategyNexthopStateLL_IncreaseTryToSwitch( - (StrategyNexthopStateLL*) state, ll->round); - } - } - } - - parcIterator_Release(&iterator); - - if(ll->bestFaces[0] == NULL){ - //we found no face so return - ll->bestFaces[0] = NULL; - ll->bestFaces[1] = NULL; - ll->use2paths = false; - goto NEW_ROUND; - } - - if(parcHashMap_Size(ll->strategy_state) == 1 || ll->avoid_multipath){ - //in this case (one face available or avoid multipath) we stop the - //search here. Just reset face 1 if needed - if(ll->bestFaces[1] != NULL){ - strategyNexthopStateLL_SetUnusedFace(ll->bestFaces[1]); - ll->bestFaces[1] = NULL; - } - ll->use2paths = false; - goto NEW_ROUND; - } - - //if we are here we have more than 1 interface, so we search for a second one - //to use in case of multipath - iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - while (parcIterator_HasNext(iterator)) { - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - if(parcUnsigned_GetUnsigned(cid) != - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])){ - - StrategyNexthopStateLL *state = (StrategyNexthopStateLL *) - parcHashMap_Get(ll->strategy_state, cid); - - if((check_losses && strategyNexthopStateLL_IsLossy(state)) || - !strategyNexthopStateLL_IsAllowed(state)){ - //skip the face - continue; - } - - if(ll->bestFaces[1] == NULL){ - //in case of 2 faces we should pass always here - ll->bestFaces[1] = state; - }else{ - //TODO this must be tested with more then 2 faces - double rtt1 = strategyNexthopStateLL_GetRTTLive(ll->bestFaces[1]); - double rttNewFace = strategyNexthopStateLL_GetRTTLive(state); - if(rttNewFace + STABILITY_FACTOR < rtt1){ - strategyNexthopStateLL_SetUnusedFace(ll->bestFaces[1]); - ll->bestFaces[1] = state; - } - } - } - } - parcIterator_Release(&iterator); - - if(ll->bestFaces[1] != NULL){ - //we are not using the second face yet so we use the normal rtt for comparison - double rtt0 = strategyNexthopStateLL_GetRTTProbe(ll->bestFaces[0]); - double rtt1 = strategyNexthopStateLL_GetRTTProbe(ll->bestFaces[1]); - double diff = fabs(rtt0 - rtt1); - if(diff < MAX_LATENCY_DIFF) { - //let's start to use 2 paths - ll->rounds_with_error = 0; - ll->use2paths = true; - ll->rounds_in_multipath = 0; - }else{ - //we use only one path - strategyNexthopStateLL_SetUnusedFace(ll->bestFaces[1]); - ll->bestFaces[1] = NULL; - ll->use2paths = false; - } - }else{ - ll->use2paths = false; - } - - NEW_ROUND: - { - Logger * log = forwarder_GetLogger(ll->forwarder); - if(log != NULL && - logger_IsLoggable(log, LoggerFacility_Strategy, PARCLogLevel_Info)){ - if(ll->use2paths){ - logger_Log(log, LoggerFacility_Strategy, PARCLogLevel_Info, - __func__, "use 2 paths. rtt face %d = %f queue = %f is_lossy = %d," - "rtt face %d = %f queue = %f is_lossy = %d\n", - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0]), - strategyNexthopStateLL_GetRTTLive(ll->bestFaces[0]), - strategyNexthopStateLL_GetQueuing(ll->bestFaces[0]), - strategyNexthopStateLL_IsLossy(ll->bestFaces[0]), - strategyNexthopStateLL_GetFaceId(ll->bestFaces[1]), - strategyNexthopStateLL_GetRTTLive(ll->bestFaces[1]), - strategyNexthopStateLL_GetQueuing(ll->bestFaces[1]), - strategyNexthopStateLL_IsLossy(ll->bestFaces[1])); - }else{ - if(ll->bestFaces[0] != NULL){ - logger_Log(log, LoggerFacility_Strategy, - PARCLogLevel_Info, __func__, - "use 1 path. rtt face %d = %f is_lossy = %d, " - "(avoid multipath = %d)\n", - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0]), - strategyNexthopStateLL_GetRTTLive(ll->bestFaces[0]), - strategyNexthopStateLL_IsLossy(ll->bestFaces[0]), - ll->avoid_multipath); - }else{ - logger_Log(log, LoggerFacility_Strategy, PARCLogLevel_Info, - __func__, "no face to use!\n"); - } - } - } - } - - //update the round only at the end for all the faces - if(new_round){ - PARCIterator * iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - while (parcIterator_HasNext(iterator)) { - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - strategyNexthopStateLL_StartNewRound((StrategyNexthopStateLL *) - parcHashMap_Get(ll->strategy_state, cid)); - } - parcIterator_Release(&iterator); - } - - //mapme updates - //if ll->bestFaces[0] == NULL we don't have any output faces - //so don't need to send any updates since we are disconnected - if(ll->related_prefixes_len != 0){ - if(ll->bestFaces[0] != NULL){ - NumberSet *out = numberSet_Create(); - if(old_faces[0] == NULL || - (strategyNexthopStateLL_GetFaceId(ll->bestFaces[0]) != - strategyNexthopStateLL_GetFaceId(old_faces[0]))){ - //there is a new face 0 so we need a map me update - //if ll->bestFaces[1] != NULL we need to send the update - //even if it is the same as before - numberSet_Add(out, - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])); - if(ll->bestFaces[1] != NULL){ - numberSet_Add(out, - strategyNexthopStateLL_GetFaceId(ll->bestFaces[1])); - } - strategyLowLatency_SendMapmeUpdate(ll,out); - }else{ - if(ll->bestFaces[1] != NULL){ - if(old_faces[1] == NULL || - (strategyNexthopStateLL_GetFaceId(ll->bestFaces[1]) != - strategyNexthopStateLL_GetFaceId(old_faces[1]))){ - //send a mapme both with face 0 and face 1 - numberSet_Add(out, - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])); - numberSet_Add(out, - strategyNexthopStateLL_GetFaceId(ll->bestFaces[1])); - strategyLowLatency_SendMapmeUpdate(ll,out); - } - }else{ - if(old_faces[1] != NULL){ - //in the previuos round we were using two faces, now only one - //send update with only face 0 - numberSet_Add(out, - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])); - strategyLowLatency_SendMapmeUpdate(ll,out); - } - } - } - numberSet_Release(&out); - } - } -} - -static void strategyLowLatency_BestFaceCB(int fd, PARCEventType which_event, - void *data){ - parcAssertTrue(which_event & PARCEventType_Timeout, - "Event incorrect, expecting %X set, got %X", - PARCEventType_Timeout, which_event); - - StrategyLowLatency * ll = (StrategyLowLatency *) data; - strategyLowLatency_SelectBestFaces(ll, true); - - struct timeval timeout = {0, 500000}; - parcEventTimer_Start(ll->computeBestFace, &timeout); -} - -StrategyImpl *strategyLowLatency_Create() { - StrategyLowLatency *strategy = - parcMemory_AllocateAndClear(sizeof(StrategyLowLatency)); - parcAssertNotNull(strategy, "parcMemory_AllocateAndClear(%zu) returned NULL", - sizeof(StrategyLowLatency)); - - strategy->strategy_state = parcHashMap_Create(); - strategy->pending_probes_ticks = parcHashMap_Create(); - strategy->pending_probes_faces = parcHashMap_Create(); -#ifndef WITH_POLICY - strategy->nexthops = numberSet_Create(); -#endif /* ! WITH_POLICY */ - srand((unsigned int)time(NULL)); - - StrategyImpl *impl = parcMemory_AllocateAndClear(sizeof(StrategyImpl)); - parcAssertNotNull(impl, "parcMemory_AllocateAndClear(%zu) returned NULL", - sizeof(StrategyImpl)); - memcpy(impl, &_template, sizeof(StrategyImpl)); - impl->context = strategy; - - return impl; -} - -void strategyLowLatency_SetStrategy(StrategyImpl *strategy, - const Forwarder * forwarder, - const FibEntry * fibEntry, - unsigned related_prefixes_len, - Name **related_prefixes) { - StrategyLowLatency *ll = - (StrategyLowLatency *)strategy->context; - ll->forwarder = forwarder; - - //create probe packet - ll->probe = messageHandler_CreateProbePacket(HF_INET6_TCP, PROBE_LIFETIME); - ip_prefix_t address; - nameBitvector_ToIPAddress(name_GetContentName( - fibEntry_GetPrefix(fibEntry)), &address); - ll->name = messageHandler_CreateProbeName(&address); - - - Dispatcher *dispatcher = forwarder_GetDispatcher((Forwarder *)ll->forwarder); - ll->sendProbes = dispatcher_CreateTimer(dispatcher, false, - strategyLowLatency_SendProbesCB, ll); - - ll->round = 0; - ll->rounds_in_multipath = 0; - ll->rounds_with_error = 0; - ll->rounds_avoiding_multipath = 0; - ll->use2paths = false; - ll->avoid_multipath = false; - - ll->related_prefixes_len = related_prefixes_len; - ll->related_prefixes = malloc(sizeof(Name *) * ll->related_prefixes_len); - for(unsigned i = 0; i < ll->related_prefixes_len; i++){ - ll->related_prefixes[i] = name_Copy(related_prefixes[i]); - } - - ll->computeBestFace = dispatcher_CreateTimer(dispatcher, false, - strategyLowLatency_BestFaceCB, ll); -} - -void _startTimers(StrategyImpl *strategy){ - StrategyLowLatency *ll = - (StrategyLowLatency *)strategy->context; - - struct timeval timeoutProbes = {0,10000}; - parcEventTimer_Start(ll->sendProbes, &timeoutProbes); - struct timeval timeoutBF = {1,0}; - parcEventTimer_Start(ll->computeBestFace, &timeoutBF); -} - -void _stopTimers(StrategyImpl *strategy){ - StrategyLowLatency *ll = - (StrategyLowLatency *)strategy->context; - - parcEventTimer_Stop(ll->sendProbes); - parcEventTimer_Stop(ll->computeBestFace); -} - -// ======================================================= -// Dispatch API - -strategy_type _strategyLowLatency_GetStrategy(StrategyImpl *strategy) { - return SET_STRATEGY_LOW_LATENCY; -} - -static void _strategyLowLatency_ReceiveObject(StrategyImpl *strategy, - const NumberSet *egressId, - const Message *objectMessage, - Ticks pitEntryCreation, - Ticks objReception) { - StrategyLowLatency *ll = (StrategyLowLatency *)strategy->context; - - if(!messageHandler_IsAProbe(message_FixedHeader(objectMessage))) - return; - - uint32_t seq = messageHandler_GetSegment(message_FixedHeader(objectMessage)); - PARCUnsigned *parc_seq = parcUnsigned_Create(seq); - if (!parcHashMap_Contains(ll->pending_probes_ticks, parc_seq)){ - parcUnsigned_Release(&parc_seq); - return; - } - - //here numberSet_Length(egressId) should be 1 - for (unsigned i = 0; i < numberSet_Length(egressId); i++) { - unsigned outId = numberSet_GetItem(egressId, i); - PARCUnsigned *cid = parcUnsigned_Create(outId); - - const StrategyNexthopStateLL *state = - parcHashMap_Get(ll->strategy_state, cid); - if (state != NULL) { - Ticks time = parcUnsigned_GetUnsigned( - parcHashMap_Get(ll->pending_probes_ticks, parc_seq)); - Ticks now = forwarder_GetTicks(ll->forwarder); - Ticks RTT = now - time; - if(RTT <= 0) - RTT = 1; - strategyNexthopStateLL_AddRttSample( - (StrategyNexthopStateLL *) state, (unsigned int)RTT); - parcHashMap_Remove(ll->pending_probes_ticks, parc_seq); - } else { - // this may happen if we remove a face/route while downloading a file - // we should ignore this timeout - } - parcUnsigned_Release(&cid); - } - parcUnsigned_Release(&parc_seq); -} - -static void _strategyLowLatency_OnTimeout(StrategyImpl *strategy, - const NumberSet *egressId) {} - -static NumberSet *_strategyLowLatency_LookupNexthop(StrategyImpl *strategy, -#ifdef WITH_POLICY - NumberSet * nexthops, -#endif /* WITH_POLICY */ - const Message *interestMessage) { - //unsigned out_connection; - NumberSet *out = numberSet_Create(); - - StrategyLowLatency *ll = (StrategyLowLatency *)strategy->context; - - //update is_allowed flag of all the next hops - PARCIterator *iterator = parcHashMap_CreateKeyIterator(ll->strategy_state); - while(parcIterator_HasNext(iterator)){ - PARCUnsigned *cid = (PARCUnsigned *) parcIterator_Next(iterator); - StrategyNexthopStateLL *state = - (StrategyNexthopStateLL *) parcHashMap_Get(ll->strategy_state, cid); - if(numberSet_Contains(nexthops, parcUnsigned_GetUnsigned(cid))){ - strategyNexthopStateLL_SetIsAllowed(state,true); - }else{ - strategyNexthopStateLL_SetIsAllowed(state,false); - } - } - parcIterator_Release(&iterator); - - if(ll->bestFaces[0] != NULL && - !strategyNexthopStateLL_IsAllowed(ll->bestFaces[0])){ - //if ll->bestFaces[0] is not allowed we need to find a new face - strategyLowLatency_SelectBestFaces(ll, false); - } - - //at this point ll->bestFaces[0] must be allowed - //single path case - if(ll->bestFaces[0] != NULL && (ll->bestFaces[1] == NULL || !ll->use2paths)){ - strategyNexthopStateLL_SendPacket(ll->bestFaces[0]); - numberSet_Add(out, strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])); - - //multipath case - }else if(ll->bestFaces[0] != NULL && ll->bestFaces[1] != NULL && ll->use2paths){ - //it may happen that ll->bestFaces[1] is not allowed, in that case we send on - //ll->bestFaces[0] until the next best face selection - if(!strategyNexthopStateLL_IsAllowed(ll->bestFaces[1])){ - strategyNexthopStateLL_SendPacket(ll->bestFaces[0]); - numberSet_Add(out, strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])); - }else{ - double queue0 = strategyNexthopStateLL_GetQueuing(ll->bestFaces[0]); - double queue1 = strategyNexthopStateLL_GetQueuing(ll->bestFaces[1]); - double prob0 = 0.5; - if(queue0 > 1 || queue1 > 1){ - prob0 = 1.0 - (queue0 / (queue0 + queue1)); - } - double coin = ((double) rand() / (RAND_MAX)); - if(coin < prob0){ - strategyNexthopStateLL_SendPacket(ll->bestFaces[0]); - numberSet_Add(out, strategyNexthopStateLL_GetFaceId(ll->bestFaces[0])); - }else{ - strategyNexthopStateLL_SendPacket(ll->bestFaces[1]); - numberSet_Add(out, strategyNexthopStateLL_GetFaceId(ll->bestFaces[1])); - } - } - } - return out; -} - - -#ifndef WITH_POLICY -static NumberSet *_strategyLowLatency_ReturnNexthops(StrategyImpl *strategy) { - StrategyLoadBalancerLL *ll = (StrategyLoadBalancerLL *)strategy->context; - return ll->nexthops; -} - -unsigned _strategyLowLatency_CountNexthops(StrategyImpl *strategy) { - StrategyLoadBalancerLL *ll = (StrategyLoadBalancerLL *)strategy->context; - return (unsigned)numberSet_Length(ll->nexthops); -} -#endif /* ! WITH_POLICY */ - -static void _strategyLowLatency_AddNexthop(StrategyImpl *strategy, - unsigned connectionId) { - PARCUnsigned *cid = parcUnsigned_Create(connectionId); - - StrategyLowLatency *ll = (StrategyLowLatency *)strategy->context; - - if (!parcHashMap_Contains(ll->strategy_state, cid)) { - StrategyNexthopStateLL *state = strategyNexthopStateLL_Create(connectionId); - parcHashMap_Put(ll->strategy_state, cid, state); - if(ll->bestFaces[0] == NULL){ - ll->bestFaces[0] = state; - } -#ifndef WITH_POLICY - numberSet_Add(ll->nexthops, connectionId); -#endif /* WITH_POLICY */ - } - - if(parcHashMap_Size(ll->strategy_state) >= 2){ - _startTimers(strategy); - } - - parcUnsigned_Release(&cid); -} - -static void _strategyLowLatency_RemoveNexthop(StrategyImpl *strategy, - unsigned connectionId) { - StrategyLowLatency *ll = (StrategyLowLatency *)strategy->context; - - bool reset_bestFaces = false; - - if((ll->bestFaces[0] != NULL && - strategyNexthopStateLL_GetFaceId(ll->bestFaces[0]) == connectionId) || - (ll->bestFaces[1] != NULL && - strategyNexthopStateLL_GetFaceId(ll->bestFaces[1]) == connectionId)){ - reset_bestFaces = true; - } - - PARCUnsigned *cid = parcUnsigned_Create(connectionId); - - if (parcHashMap_Contains(ll->strategy_state, cid)) { - parcHashMap_Remove(ll->strategy_state, cid); -#ifndef WITH_POLICY - numberSet_Remove(lb->nexthops, connectionId); -#endif /* WITH_POLICY */ - } - - if(reset_bestFaces){ - ll->bestFaces[0] = NULL; - ll->bestFaces[1] = NULL; - strategyLowLatency_SelectBestFaces(ll, false); - } - - if(parcHashMap_Size(ll->strategy_state) < 2){ - _stopTimers(strategy); - } - - parcUnsigned_Release(&cid); -} - -static void _strategyLowLatency_ImplDestroy(StrategyImpl **strategyPtr) { - parcAssertNotNull(strategyPtr, "Parameter must be non-null double pointer"); - parcAssertNotNull(*strategyPtr, - "Parameter must dereference to non-null pointer"); - - StrategyImpl *impl = *strategyPtr; - StrategyLowLatency *strategy = (StrategyLowLatency *)impl->context; - - _stopTimers(impl); - - parcEventTimer_Destroy(&(strategy->sendProbes)); - parcEventTimer_Destroy(&(strategy->computeBestFace)); - - if (parcHashMap_Size(strategy->strategy_state) > 0) { - PARCIterator *it = parcHashMap_CreateKeyIterator(strategy->strategy_state); - while (parcIterator_HasNext(it)) { - PARCUnsigned *cid = parcIterator_Next(it); - StrategyNexthopStateLL *state = - (StrategyNexthopStateLL *)parcHashMap_Get(strategy->strategy_state, cid); - parcObject_Release((void**)&state); - } - parcIterator_Release(&it); - } - - parcHashMap_Release(&(strategy->strategy_state)); - parcHashMap_Release(&(strategy->pending_probes_ticks)); - parcHashMap_Release(&(strategy->pending_probes_faces)); - - parcMemory_Deallocate(&(strategy->probe)); - parcMemory_Deallocate(&(strategy->name)); - - for(unsigned i = 0; i < strategy->related_prefixes_len; i++){ - name_Release(&(strategy->related_prefixes[i])); - } - free(strategy->related_prefixes); - -#ifndef WITH_POLICY - numberSet_Release(&(strategy->nexthops)); -#endif /* ! WITH_POLICY */ - - parcMemory_Deallocate((void **)&strategy); - parcMemory_Deallocate((void **)&impl); - *strategyPtr = NULL; -} |