Multiple DNS threads

Makefile

@@ -1,14 +1,10 @@
 dnsseed: dns.o bitcoin.o netbase.o protocol.o db.o main.o
 	g++ -pthread -lcrypto -o dnsseed dns.o bitcoin.o netbase.o protocol.o db.o main.o
-	strip -s dnsseed
-
-dnsseed.dbg: dns.o bitcoin.o netbase.o protocol.o db.o main.o
-	g++ -pthread -lcrypto -o dnsseed.dbg dns.o bitcoin.o netbase.o protocol.o db.o main.o
 
 %.o: %.cpp bitcoin.h netbase.h protocol.h db.h serialize.h uint256.h util.h
-	g++ -pthread -O3 -ggdb3 -march=nocona -Wno-invalid-offsetof -c -o $@ $<
+	g++ -pthread -O2 -ggdb3 -march=nocona -Wno-invalid-offsetof -c -o $@ $<
 
 dns.o: dns.c
-	gcc -pthread -std=c99 -O3 -g0 -march=nocona dns.c -c -o dns.o
+	gcc -pthread -std=c99 -O2 -ggdb3 -march=nocona dns.c -c -o dns.o
 
 %.o: %.cpp

dns.c

@@ -296,7 +296,7 @@ ssize_t static dnshandle(dns_opt_t *opt, const unsigned char *inbuf, size_t insi
   // A records
   if ((typ == TYPE_A || typ == QTYPE_ANY) && (cls == CLASS_IN || cls == QCLASS_ANY)) {
     struct in_addr addr[32];
-    int naddr = opt->cb(addr, 32, 1);
+    int naddr = opt->cb((void*)opt, addr, 32, 1);
     int n = 0;
     while (n < naddr) {
       int ret = write_record_a(&outpos, outend - auth_size, "", offset, CLASS_IN, opt->datattl, &addr[n]);
@@ -333,27 +333,39 @@ error:
   return 12;
 }
 
+static int listenSocket = -1;
+
 int dnsserver(dns_opt_t *opt) {
-  struct sockaddr_in si_me, si_other;
-  socklen_t s, slen=sizeof(si_other);
+  struct sockaddr_in si_other;
+  int senderSocket = -1;
+  senderSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+  if (senderSocket == -1) 
+    return -3;
+
+  if (listenSocket == -1) {
+    struct sockaddr_in si_me;
+    if ((listenSocket=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1) {
+      listenSocket = -1;
+      return -1;
+    }
+    memset((char *) &si_me, 0, sizeof(si_me));
+    si_me.sin_family = AF_INET;
+    si_me.sin_port = htons(opt->port);
+    si_me.sin_addr.s_addr = INADDR_ANY;
+    if (bind(listenSocket, (struct sockaddr*)&si_me, sizeof(si_me))==-1)
+      return -2;
+  }
   unsigned char inbuf[BUFLEN], outbuf[BUFLEN];
-  if ((s=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
-    return -1;
-  memset((char *) &si_me, 0, sizeof(si_me));
-  si_me.sin_family = AF_INET;
-  si_me.sin_port = htons(opt->port);
-  si_me.sin_addr.s_addr = INADDR_ANY;
-  if (bind(s, (struct sockaddr*)&si_me, sizeof(si_me))==-1)
-    return -2;
   do {
-    ssize_t insize = recvfrom(s, inbuf, BUFLEN, 0, (struct sockaddr*)&si_other, &slen);
+    socklen_t si_other_len = sizeof(si_other);
+    ssize_t insize = recvfrom(listenSocket, inbuf, BUFLEN, 0, (struct sockaddr*)&si_other, &si_other_len);
     unsigned char *addr = (unsigned char*)&si_other.sin_addr.s_addr;
 //    printf("DNS: Request %llu from %i.%i.%i.%i:%i of %i bytes\n", (unsigned long long)(opt->nRequests), addr[0], addr[1], addr[2], addr[3], ntohs(si_other.sin_port), (int)insize);
     opt->nRequests++;
     if (insize > 0) {
       ssize_t ret = dnshandle(opt, inbuf, insize, outbuf);
       if (ret > 0)
-        sendto(s, outbuf, ret, 0, (struct sockaddr*)&si_other, slen);
+        sendto(listenSocket, outbuf, ret, 0, (struct sockaddr*)&si_other, sizeof(si_other));
     }
   } while(1);
   return 0;

dns.h

@@ -10,7 +10,7 @@ typedef struct {
   const char *host;
   const char *ns;
   const char *mbox;
-  int (*cb)(struct in_addr *addr, int max, int ipv4only);
+  int (*cb)(void *opt, struct in_addr *addr, int max, int ipv4only);
   // stats
   uint64_t nRequests;
 } dns_opt_t;

main.cpp

@@ -16,11 +16,12 @@ class CDnsSeedOpts {
 public:
   int nThreads;
   int nPort;
+  int nDnsThreads;
   const char *mbox;
   const char *ns;
   const char *host;
   
-  CDnsSeedOpts() : nThreads(24), nPort(53), mbox(NULL), ns(NULL), host(NULL) {}
+  CDnsSeedOpts() : nThreads(24), nDnsThreads(24), nPort(53), mbox(NULL), ns(NULL), host(NULL) {}
   
   void ParseCommandLine(int argc, char **argv) {
     static const char *help = "Bitcoin-seeder\n"
@@ -31,6 +32,7 @@ public:
                               "-n <ns>         Hostname of the nameserver\n"
                               "-m <mbox>       E-Mail address reported in SOA records\n"
                               "-t <threads>    Number of crawlers to run in parallel (default 24)\n"
+                              "-d <threads>    Number of DNS server threads (default 24)\n"
                               "-p <port>       UDP port to listen on (default 53)\n"
                               "-?, --help      Show this text\n"
                               "\n";
@@ -42,12 +44,13 @@ public:
         {"ns",   required_argument, 0, 'n'},
         {"mbox", required_argument, 0, 'm'},
         {"threads", required_argument, 0, 't'},
+        {"dnsthreads", required_argument, 0, 'd'},
         {"port", required_argument, 0, 'p'},
         {"help", no_argument, 0, 'h'},
         {0, 0, 0, 0}
       };
       int option_index = 0;
-      int c = getopt_long(argc, argv, "h:n:m:t:p:", long_options, &option_index);
+      int c = getopt_long(argc, argv, "h:n:m:t:p:d:", long_options, &option_index);
       if (c == -1) break;
       switch (c) {
         case 'h': {
@@ -71,6 +74,12 @@ public:
           break;
         }
 
+        case 'd': {
+          int n = strtol(optarg, NULL, 10);
+          if (n > 0 && n < 1000) nDnsThreads = n;
+          break;
+        }
+
         case 'p': {
           int p = strtol(optarg, NULL, 10);
           if (p > 0 && p < 65536) nPort = p;
@@ -118,57 +127,78 @@ extern "C" void* ThreadCrawler(void* data) {
   } while(1);
 }
 
-static vector<struct in_addr> cache;
-static time_t cacheTime;
-static unsigned int cacheHits = 1000000000;
-static uint64_t dbQueries = 0;
+extern "C" int GetIPList(void *thread, struct in_addr *addr, int max, int ipv4only);
 
-void static cacheRefresh(int ipv4only) {
-  time_t now = time(NULL);
-  cacheHits++;
-  if (cacheHits > (cache.size()*cache.size()/400) || (cacheHits*cacheHits > cache.size() / 20 && (now - cacheTime > 5))) {
-    set<CIP> ips;
-    db.GetIPs(ips, 1000, ipv4only);
-    dbQueries++;
-    cache.clear();
-    cache.reserve(ips.size());
-    for (set<CIP>::iterator it = ips.begin(); it != ips.end(); it++) {
-      struct in_addr addr;
-      if ((*it).GetInAddr(&addr)) {
-        cache.push_back(addr);
+class CDnsThread {
+public:
+  dns_opt_t dns_opt;
+  vector<struct in_addr> cache;
+  time_t cacheTime;
+  unsigned int cacheHits;
+  uint64_t dbQueries;
+
+  void cacheHit(int ipv4only, bool force = false) {
+    time_t now = time(NULL);
+    cacheHits++;
+    if (force || cacheHits > (cache.size()*cache.size()/400) || (cacheHits*cacheHits > cache.size() / 20 && (now - cacheTime > 5))) {
+      set<CIP> ips;
+      db.GetIPs(ips, 1000, ipv4only);
+      dbQueries++;
+      cache.clear();
+      cache.reserve(ips.size());
+      for (set<CIP>::iterator it = ips.begin(); it != ips.end(); it++) {
+        struct in_addr addr;
+        if ((*it).GetInAddr(&addr)) {
+          cache.push_back(addr);
+        }
       }
+      cacheHits = 0;
+      cacheTime = now;
     }
+  }
+
+  CDnsThread(CDnsSeedOpts* opts) {
+    dns_opt.host = opts->host;
+    dns_opt.ns = opts->ns;
+    dns_opt.mbox = opts->mbox;
+    dns_opt.datattl = 60;
+    dns_opt.nsttl = 40000;
+    dns_opt.cb = GetIPList;
+    dns_opt.port = opts->nPort;
+    dns_opt.nRequests = 0;
+    cache.clear();
+    cache.reserve(1000);
+    cacheTime = 0;
     cacheHits = 0;
-    cacheTime = now;
+    dbQueries = 0;
+    cacheHit(true, true);
   }
-}
 
-extern "C" int GetIPList(struct in_addr *addr, int max, int ipv4only) {
-  cacheRefresh(ipv4only);
-  if (max > cache.size())
-    max = cache.size();
+  void run() {
+    dnsserver(&dns_opt);
+  }
+};
+
+extern "C" int GetIPList(void *data, struct in_addr *addr, int max, int ipv4only) {
+  CDnsThread *thread = (CDnsThread*)data;
+  thread->cacheHit(ipv4only);
+  unsigned int size = thread->cache.size();
+  if (max > size)
+    max = size;
   for (int i=0; i<max; i++) {
-    int j = i + (rand() % (cache.size() - i));
-    addr[i] = cache[j];
-    cache[j] = cache[i];
-    cache[i] = addr[i];
+    int j = i + (rand() % (size - i));
+    addr[i] = thread->cache[j];
+    thread->cache[j] = thread->cache[i];
+    thread->cache[i] = addr[i];
   }
   return max;
 }
 
-static dns_opt_t dns_opt;
+vector<CDnsThread*> dnsThread;
 
 extern "C" void* ThreadDNS(void* arg) {
-  CDnsSeedOpts *opts = (CDnsSeedOpts*)arg;
-  dns_opt.host = opts->host;
-  dns_opt.ns = opts->ns;
-  dns_opt.mbox = opts->mbox;
-  dns_opt.datattl = 60;
-  dns_opt.nsttl = 40000;
-  dns_opt.cb = GetIPList;
-  dns_opt.port = opts->nPort;
-  dns_opt.nRequests = 0;
-  dnsserver(&dns_opt);
+  CDnsThread *thread = (CDnsThread*)arg;
+  thread->run();
 }
 
 int StatCompare(const CAddrReport& a, const CAddrReport& b) {
@@ -223,7 +253,13 @@ extern "C" void* ThreadStats(void*) {
     CAddrDbStats stats;
     db.GetStats(stats);
     printf("\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b");
-    printf("%s %i/%i available (%i tried in %is, %i new, %i active), %i banned; %llu DNS requests, %llu db reads", c, stats.nGood, stats.nAvail, stats.nTracked, stats.nAge, stats.nNew, stats.nAvail - stats.nTracked - stats.nNew, stats.nBanned, (unsigned long long)dns_opt.nRequests, (unsigned long long)dbQueries);
+    uint64_t requests = 0;
+    uint64_t queries = 0;
+    for (unsigned int i=0; i<dnsThread.size(); i++) {
+      requests += dnsThread[i]->dns_opt.nRequests;
+      queries += dnsThread[i]->dbQueries;
+    }
+    printf("%s %i/%i available (%i tried in %is, %i new, %i active), %i banned; %llu DNS requests, %llu db queries", c, stats.nGood, stats.nAvail, stats.nTracked, stats.nAge, stats.nNew, stats.nAvail - stats.nTracked - stats.nNew, stats.nBanned, (unsigned long long)requests, (unsigned long long)queries);
     Sleep(1000);
   } while(1);
 }
@@ -276,8 +312,14 @@ int main(int argc, char **argv) {
   printf("done\n");
   pthread_create(&threadDump, NULL, ThreadDumper, NULL);
   if (fDNS) {
-    printf("Starting DNS server for %s on %s (port %i)...", opts.host, opts.ns, opts.nPort);
-    pthread_create(&threadDns, NULL, ThreadDNS, &opts);
+    printf("Starting %i DNS threads for %s on %s (port %i)...", opts.nDnsThreads, opts.host, opts.ns, opts.nPort);
+    dnsThread.clear();
+    for (int i=0; i<opts.nDnsThreads; i++) {
+      dnsThread.push_back(new CDnsThread(&opts));
+      pthread_create(&threadDns, NULL, ThreadDNS, dnsThread[i]);
+      printf(".");
+      Sleep(20);
+    }
     printf("done\n");
   }
   pthread_create(&threadStats, NULL, ThreadStats, NULL);