mirror of
https://github.com/zerotier/ZeroTierOne.git
synced 2024-12-23 23:02:23 +00:00
Replace slow std::list<> with an O(log(N)) data structure for the cluster relaying send queue.
This commit is contained in:
Adam Ierymenko
parent
32ec378e3b
commit
b171c9a0db
226
node/Cluster.cpp
226
node/Cluster.cpp
@ -33,8 +33,12 @@
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#include <string.h>
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#include <math.h>
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#include <map>
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#include <algorithm>
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#include <set>
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#include <utility>
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#include <list>
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#include <stdexcept>
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#include "../version.h"
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@ -49,6 +53,34 @@
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#include "Packet.hpp"
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#include "Switch.hpp"
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#include "Node.hpp"
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#include "Array.hpp"
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/**
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* Chunk size for allocating queue entries
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*
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* Queue entries are allocated in chunks of this many and are added to a pool.
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* ZT_CLUSTER_MAX_QUEUE_GLOBAL must be evenly divisible by this.
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*/
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#define ZT_CLUSTER_QUEUE_CHUNK_SIZE 32
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/**
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* Maximum number of chunks to ever allocate
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*
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* This is a global sanity limit to prevent resource exhaustion attacks. It
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* works out to about 600mb of RAM. You'll never see this on a normal edge
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* node. We're unlikely to see this on a root server unless someone is DOSing
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* us. In that case cluster relaying will be affected but other functions
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* should continue to operate normally.
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*/
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#define ZT_CLUSTER_MAX_QUEUE_CHUNKS 8194
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/**
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* Max data per queue entry
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*
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* If we ever support larger transport MTUs this must be increased. The plus
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* 16 is just a small margin and has no special meaning.
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*/
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#define ZT_CLUSTER_SEND_QUEUE_DATA_MAX (ZT_UDP_DEFAULT_PAYLOAD_MTU + 16)
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namespace ZeroTier {
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@ -61,6 +93,137 @@ static inline double _dist3d(int x1,int y1,int z1,int x2,int y2,int z2)
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return sqrt((dx * dx) + (dy * dy) + (dz * dz));
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}
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// An entry in _ClusterSendQueue
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struct _ClusterSendQueueEntry
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{
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uint64_t timestamp;
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Address fromPeerAddress;
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Address toPeerAddress;
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// if we ever support larger transport MTUs this must be increased
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unsigned char data[ZT_CLUSTER_SEND_QUEUE_DATA_MAX];
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unsigned int len;
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bool unite;
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};
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// A multi-index map with entry memory pooling -- this allows our queue to
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// be O(log(N)) and is complex enough that it makes the code a lot cleaner
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// to break it out from Cluster.
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class _ClusterSendQueue
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{
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public:
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_ClusterSendQueue() :
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_poolCount(0)
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{
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}
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~_ClusterSendQueue() {} // memory is automatically freed when _chunks is destroyed
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inline void enqueue(uint64_t ts,const Address &from,const Address &to,const void *data,unsigned int len,bool unite)
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{
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if (len > ZT_CLUSTER_SEND_QUEUE_DATA_MAX)
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return;
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Mutex::Lock _l(_lock);
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// Delete oldest queue entry if sender has too many queued packets
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{
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std::set< std::pair<Address,_ClusterSendQueueEntry *> >::iterator qi(_bySrc.lower_bound(std::pair<Address,_ClusterSendQueueEntry *>(from,(_ClusterSendQueueEntry *)0)));
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std::set< std::pair<Address,_ClusterSendQueueEntry *> >::iterator oldest(_bySrc.end());
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unsigned long countForSender = 0;
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while ((qi != _bySrc.end())&&(qi->first == from)) {
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if (++countForSender > ZT_CLUSTER_MAX_QUEUE_PER_SENDER) {
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_byDest.erase(std::pair<Address,_ClusterSendQueueEntry *>(oldest->second->toPeerAddress,oldest->second));
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_pool[_poolCount++] = oldest->second;
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_bySrc.erase(oldest);
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break;
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} else if (oldest == _bySrc.end())
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oldest = qi;
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++qi;
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}
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}
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_ClusterSendQueueEntry *e;
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if (_poolCount > 0) {
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e = _pool[--_poolCount];
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} else {
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if (_chunks.size() >= ZT_CLUSTER_MAX_QUEUE_CHUNKS)
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return; // queue is totally full!
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_chunks.push_back(Array<_ClusterSendQueueEntry,ZT_CLUSTER_QUEUE_CHUNK_SIZE>());
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e = &(_chunks.back().data[0]);
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for(unsigned int i=1;i<ZT_CLUSTER_QUEUE_CHUNK_SIZE;++i)
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_pool[_poolCount++] = &(_chunks.back().data[i]);
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}
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e->timestamp = ts;
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e->fromPeerAddress = from;
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e->toPeerAddress = to;
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memcpy(e->data,data,len);
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e->len = len;
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e->unite = unite;
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_bySrc.insert(std::pair<Address,_ClusterSendQueueEntry *>(from,e));
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_byDest.insert(std::pair<Address,_ClusterSendQueueEntry *>(to,e));
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}
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inline void expire(uint64_t now)
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{
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Mutex::Lock _l(_lock);
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for(std::set< std::pair<Address,_ClusterSendQueueEntry *> >::iterator qi(_bySrc.begin());qi!=_bySrc.end();) {
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if ((now - qi->second->timestamp) > ZT_CLUSTER_QUEUE_EXPIRATION) {
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_byDest.erase(std::pair<Address,_ClusterSendQueueEntry *>(qi->second->toPeerAddress,qi->second));
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_pool[_poolCount++] = qi->second;
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_bySrc.erase(qi++);
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} else ++qi;
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}
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}
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/**
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* Get and dequeue entries for a given destination address
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*
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* After use these entries must be returned with returnToPool()!
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*
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* @param dest Destination address
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* @param results Array to fill with results
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* @param maxResults Size of results[] in pointers
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* @return Number of actual results returned
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*/
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inline unsigned int getByDest(const Address &dest,_ClusterSendQueueEntry **results,unsigned int maxResults)
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{
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unsigned int count = 0;
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Mutex::Lock _l(_lock);
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std::set< std::pair<Address,_ClusterSendQueueEntry *> >::iterator qi(_byDest.lower_bound(std::pair<Address,_ClusterSendQueueEntry *>(dest,(_ClusterSendQueueEntry *)0)));
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while ((qi != _byDest.end())&&(qi->first == dest)) {
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_bySrc.erase(std::pair<Address,_ClusterSendQueueEntry *>(qi->second->fromPeerAddress,qi->second));
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results[count++] = qi->second;
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if (count == maxResults)
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break;
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_byDest.erase(qi++);
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}
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return count;
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}
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/**
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* Return entries to pool after use
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*
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* @param entries Array of entries
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* @param count Number of entries
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*/
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inline void returnToPool(_ClusterSendQueueEntry **entries,unsigned int count)
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{
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Mutex::Lock _l(_lock);
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for(unsigned int i=0;i<count;++i)
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_pool[_poolCount++] = entries[i];
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}
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private:
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std::list< Array<_ClusterSendQueueEntry,ZT_CLUSTER_QUEUE_CHUNK_SIZE> > _chunks;
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_ClusterSendQueueEntry *_pool[ZT_CLUSTER_QUEUE_CHUNK_SIZE * ZT_CLUSTER_MAX_QUEUE_CHUNKS];
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unsigned long _poolCount;
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std::set< std::pair<Address,_ClusterSendQueueEntry *> > _bySrc;
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std::set< std::pair<Address,_ClusterSendQueueEntry *> > _byDest;
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Mutex _lock;
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};
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Cluster::Cluster(
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const RuntimeEnvironment *renv,
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uint16_t id,
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@ -73,6 +236,7 @@ Cluster::Cluster(
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int (*addressToLocationFunction)(void *,const struct sockaddr_storage *,int *,int *,int *),
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void *addressToLocationFunctionArg) :
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RR(renv),
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_sendQueue(new _ClusterSendQueue()),
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_sendFunction(sendFunction),
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_sendFunctionArg(sendFunctionArg),
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_addressToLocationFunction(addressToLocationFunction),
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@ -84,7 +248,8 @@ Cluster::Cluster(
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_zeroTierPhysicalEndpoints(zeroTierPhysicalEndpoints),
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_members(new _Member[ZT_CLUSTER_MAX_MEMBERS]),
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_lastFlushed(0),
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_lastCleanedRemotePeers(0)
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_lastCleanedRemotePeers(0),
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_lastCleanedQueue(0)
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{
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uint16_t stmp[ZT_SHA512_DIGEST_LEN / sizeof(uint16_t)];
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@ -105,6 +270,7 @@ Cluster::~Cluster()
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Utils::burn(_masterSecret,sizeof(_masterSecret));
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Utils::burn(_key,sizeof(_key));
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delete [] _members;
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delete _sendQueue;
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}
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void Cluster::handleIncomingStateMessage(const void *msg,unsigned int len)
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@ -220,19 +386,13 @@ void Cluster::handleIncomingStateMessage(const void *msg,unsigned int len)
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_remotePeers[std::pair<Address,unsigned int>(id.address(),(unsigned int)fromMemberId)] = RR->node->now();
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}
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std::list<_SQE> q;
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{
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Mutex::Lock _l(_sendViaClusterQueue_m);
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for(std::list<_SQE>::iterator qi(_sendViaClusterQueue.begin());qi!=_sendViaClusterQueue.end();) {
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if (qi->toPeerAddress == id.address())
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q.splice(q.end(),_sendViaClusterQueue,qi++);
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else ++qi;
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}
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}
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for(std::list<_SQE>::iterator qi(q.begin());qi!=q.end();++qi)
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this->sendViaCluster(id.address(),qi->toPeerAddress,qi->data,qi->len,qi->unite);
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_ClusterSendQueueEntry *q[16384]; // 16384 is "tons"
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unsigned int qc = _sendQueue->getByDest(id.address(),q,16384);
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for(unsigned int i=0;i<qc;++i)
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this->sendViaCluster(q[i]->fromPeerAddress,q[i]->toPeerAddress,q[i]->data,q[i]->len,q[i]->unite);
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_sendQueue->returnToPool(q,qc);
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TRACE("[%u] has %s (retried %u queued sends)",(unsigned int)fromMemberId,id.address().toString().c_str(),(unsigned int)q.size());
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TRACE("[%u] has %s (retried %u queued sends)",(unsigned int)fromMemberId,id.address().toString().c_str(),qc);
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}
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} break;
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@ -244,7 +404,6 @@ void Cluster::handleIncomingStateMessage(const void *msg,unsigned int len)
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peer->identity().serialize(buf);
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Mutex::Lock _l2(_members[fromMemberId].lock);
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_send(fromMemberId,CLUSTER_MESSAGE_HAVE_PEER,buf.data(),buf.size());
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_flush(fromMemberId);
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}
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} break;
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@ -333,7 +492,6 @@ void Cluster::handleIncomingStateMessage(const void *msg,unsigned int len)
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{
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Mutex::Lock _l2(_members[fromMemberId].lock);
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_send(fromMemberId,CLUSTER_MESSAGE_PROXY_SEND,rendezvousForRemote.data(),rendezvousForRemote.size());
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_flush(fromMemberId);
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}
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RR->sw->send(rendezvousForLocal,true,0);
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}
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@ -379,19 +537,6 @@ void Cluster::sendViaCluster(const Address &fromPeerAddress,const Address &toPee
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if (len > ZT_PROTO_MAX_PACKET_LENGTH) // sanity check
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return;
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unsigned int queueCount = 0;
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{
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Mutex::Lock _l(_sendViaClusterQueue_m);
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for(std::list<_SQE>::const_iterator qi(_sendViaClusterQueue.begin());qi!=_sendViaClusterQueue.end();++qi) {
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if (qi->fromPeerAddress == fromPeerAddress) {
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if (++queueCount > ZT_CLUSTER_MAX_QUEUE_PER_SENDER) {
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TRACE("dropping sendViaCluster for %s -> %s since queue for sender is full",fromPeerAddress.toString().c_str(),toPeerAddress.toString().c_str());
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return;
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}
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}
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}
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}
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const uint64_t now = RR->node->now();
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uint64_t mostRecentTs = 0;
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@ -423,8 +568,6 @@ void Cluster::sendViaCluster(const Address &fromPeerAddress,const Address &toPee
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for(std::vector<uint16_t>::const_iterator mid(_memberIds.begin());mid!=_memberIds.end();++mid) {
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Mutex::Lock _l2(_members[*mid].lock);
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_send(*mid,CLUSTER_MESSAGE_WANT_PEER,tmp,ZT_ADDRESS_LENGTH);
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if ((enqueueAndWait)&&(queueCount == 0))
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_flush(*mid);
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}
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}
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@ -432,8 +575,7 @@ void Cluster::sendViaCluster(const Address &fromPeerAddress,const Address &toPee
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// later and return after having broadcasted a WANT_PEER.
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if (enqueueAndWait) {
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TRACE("sendViaCluster %s -> %s enqueueing to wait for HAVE_PEER",fromPeerAddress.toString().c_str(),toPeerAddress.toString().c_str());
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Mutex::Lock _l(_sendViaClusterQueue_m);
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_sendViaClusterQueue.push_back(_SQE(now,fromPeerAddress,toPeerAddress,data,len,unite));
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_sendQueue->enqueue(now,fromPeerAddress,toPeerAddress,data,len,unite);
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return;
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}
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}
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@ -464,10 +606,8 @@ void Cluster::sendViaCluster(const Address &fromPeerAddress,const Address &toPee
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{
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Mutex::Lock _l2(_members[mostRecentMemberId].lock);
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if (buf.size() > 0) {
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if (buf.size() > 0)
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_send(mostRecentMemberId,CLUSTER_MESSAGE_PROXY_UNITE,buf.data(),buf.size());
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_flush(mostRecentMemberId);
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}
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if (_members[mostRecentMemberId].zeroTierPhysicalEndpoints.size() > 0) {
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TRACE("sendViaCluster relaying %u bytes from %s to %s by way of %u",len,fromPeerAddress.toString().c_str(),toPeerAddress.toString().c_str(),(unsigned int)mostRecentMemberId);
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RR->node->putPacket(InetAddress(),_members[mostRecentMemberId].zeroTierPhysicalEndpoints.front(),data,len);
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@ -484,7 +624,6 @@ void Cluster::sendDistributedQuery(const Packet &pkt)
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for(std::vector<uint16_t>::const_iterator mid(_memberIds.begin());mid!=_memberIds.end();++mid) {
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Mutex::Lock _l2(_members[*mid].lock);
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_send(*mid,CLUSTER_MESSAGE_REMOTE_PACKET,buf.data(),buf.size());
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_flush(*mid);
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}
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}
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@ -495,15 +634,6 @@ void Cluster::doPeriodicTasks()
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if ((now - _lastFlushed) >= ZT_CLUSTER_FLUSH_PERIOD) {
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_lastFlushed = now;
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{
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Mutex::Lock _l2(_sendViaClusterQueue_m);
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for(std::list<_SQE>::iterator qi(_sendViaClusterQueue.begin());qi!=_sendViaClusterQueue.end();) {
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if ((now - qi->timestamp) >= ZT_CLUSTER_QUEUE_EXPIRATION)
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_sendViaClusterQueue.erase(qi++);
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else ++qi;
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}
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}
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Mutex::Lock _l(_memberIds_m);
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for(std::vector<uint16_t>::const_iterator mid(_memberIds.begin());mid!=_memberIds.end();++mid) {
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Mutex::Lock _l2(_members[*mid].lock);
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@ -549,6 +679,11 @@ void Cluster::doPeriodicTasks()
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else ++rp;
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}
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}
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if ((now - _lastCleanedQueue) >= ZT_CLUSTER_QUEUE_EXPIRATION) {
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_lastCleanedQueue = now;
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_sendQueue->expire(now);
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}
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}
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void Cluster::addMember(uint16_t memberId)
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@ -768,7 +903,6 @@ void Cluster::_doREMOTE_WHOIS(uint64_t fromMemberId,const Packet &remotep)
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TRACE("responding to remote WHOIS from %s @ %u with identity of %s",remotep.source().toString().c_str(),(unsigned int)fromMemberId,queried.address().toString().c_str());
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Mutex::Lock _l2(_members[fromMemberId].lock);
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_send(fromMemberId,CLUSTER_MESSAGE_PROXY_SEND,routp.data(),routp.size());
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_flush(fromMemberId);
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}
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}
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}
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@ -30,16 +30,11 @@
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#ifdef ZT_ENABLE_CLUSTER
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#include <vector>
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#include <algorithm>
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#include <map>
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#include <utility>
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#include <list>
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#include "Constants.hpp"
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#include "../include/ZeroTierOne.h"
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#include "Address.hpp"
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#include "Array.hpp"
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#include "InetAddress.hpp"
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#include "SHA512.hpp"
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#include "Utils.hpp"
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@ -48,6 +43,7 @@
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#include "SharedPtr.hpp"
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#include "Hashtable.hpp"
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#include "Packet.hpp"
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#include "SharedPtr.hpp"
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/**
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* Timeout for cluster members being considered "alive"
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@ -60,12 +56,12 @@
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/**
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* Desired period between doPeriodicTasks() in milliseconds
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*/
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#define ZT_CLUSTER_PERIODIC_TASK_PERIOD 100
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#define ZT_CLUSTER_PERIODIC_TASK_PERIOD 25
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/**
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* How often to flush outgoing message queues (maximum interval)
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*/
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#define ZT_CLUSTER_FLUSH_PERIOD 250
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#define ZT_CLUSTER_FLUSH_PERIOD 100
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/**
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* Maximum number of queued outgoing packets per sender address
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@ -75,7 +71,7 @@
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/**
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* Expiration time for send queue entries
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*/
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#define ZT_CLUSTER_QUEUE_EXPIRATION 500
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#define ZT_CLUSTER_QUEUE_EXPIRATION 1500
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namespace ZeroTier {
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@ -84,6 +80,9 @@ class MulticastGroup;
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class Peer;
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class Identity;
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// Internal class implemented inside Cluster.cpp
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class _ClusterSendQueue;
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/**
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* Multi-homing cluster state replication and packet relaying
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*
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@ -323,10 +322,11 @@ private:
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void _doREMOTE_WHOIS(uint64_t fromMemberId,const Packet &remotep);
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void _doREMOTE_MULTICAST_GATHER(uint64_t fromMemberId,const Packet &remotep);
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// These are initialized in the constructor and remain immutable
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// These are initialized in the constructor and remain immutable ------------
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uint16_t _masterSecret[ZT_SHA512_DIGEST_LEN / sizeof(uint16_t)];
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unsigned char _key[ZT_PEER_SECRET_KEY_LENGTH];
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const RuntimeEnvironment *RR;
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_ClusterSendQueue *const _sendQueue;
|
||||
void (*_sendFunction)(void *,unsigned int,const void *,unsigned int);
|
||||
void *_sendFunctionArg;
|
||||
int (*_addressToLocationFunction)(void *,const struct sockaddr_storage *,int *,int *,int *);
|
||||
@ -336,7 +336,7 @@ private:
|
||||
const int32_t _z;
|
||||
const uint16_t _id;
|
||||
const std::vector<InetAddress> _zeroTierPhysicalEndpoints;
|
||||
// end immutable fields
|
||||
// end immutable fields -----------------------------------------------------
|
||||
|
||||
struct _Member
|
||||
{
|
||||
@ -379,27 +379,9 @@ private:
|
||||
std::map< std::pair<Address,unsigned int>,uint64_t > _remotePeers; // we need ordered behavior and lower_bound here
|
||||
Mutex _remotePeers_m;
|
||||
|
||||
struct _SQE
|
||||
{
|
||||
_SQE() : timestamp(0),len(0),unite(false) {}
|
||||
_SQE(const uint64_t ts,const Address &f,const Address &t,const void *d,const unsigned int l,const bool u) :
|
||||
timestamp(ts),
|
||||
fromPeerAddress(f),
|
||||
toPeerAddress(t),
|
||||
len(l),
|
||||
unite(u) { memcpy(data,d,l); }
|
||||
uint64_t timestamp;
|
||||
Address fromPeerAddress;
|
||||
Address toPeerAddress;
|
||||
unsigned int len;
|
||||
bool unite;
|
||||
unsigned char data[ZT_PROTO_MAX_PACKET_LENGTH];
|
||||
};
|
||||
std::list<_SQE> _sendViaClusterQueue;
|
||||
Mutex _sendViaClusterQueue_m;
|
||||
|
||||
uint64_t _lastFlushed;
|
||||
uint64_t _lastCleanedRemotePeers;
|
||||
uint64_t _lastCleanedQueue;
|
||||
};
|
||||
|
||||
} // namespace ZeroTier
|
||||
|
||||
Loading…
Reference in New Issue
Block a user