Changeset 1505

Timestamp:

02/01/10 22:54:44 (6 weeks ago)

Author:

ahu

Message:

implement explicit (configurable) limit to number of mthreads - we are usually implicitly limited, this is no change of behaviour for almost all setups

Location:

trunk/pdns/pdns

Files:

• pdns_recursor.cc (modified) (7 diffs)
• syncres.hh (modified) (1 diff)

trunk/pdns/pdns/pdns_recursor.cc

@@ -107 +107 @@
 tcpListenSockets_t g_tcpListenSockets;   // shared across threads, but this is fine, never written to from a thread. All threads listen on all sockets
 int g_tcpTimeout;
+unsigned int g_maxMThreads;
 struct timeval g_now; // timestamp, updated (too) frequently
 map<int, ComboAddress> g_listenSocketsAddresses; // is shared across all threads right now
@@ -750 +751 @@
   int newsock=(int)accept(fd, (struct sockaddr*)&addr, &addrlen);
   if(newsock>0) {
+    if(MT->numProcesses() > g_maxMThreads) {
+      g_stats.overCapacityDrops++;
+      Utility::closesocket(newsock);
+      return;
+    }
+
     g_stats.addRemote(addr);
     if(t_allowFrom && !t_allowFrom->match(&addr)) {
@@ -788 +795 @@
   socklen_t addrlen=sizeof(fromaddr);
 
+  
   if((len=recvfrom(fd, data, sizeof(data), 0, (sockaddr *)&fromaddr, &addrlen)) >= 0) {
+
     g_stats.addRemote(fromaddr);
 
@@ -825 +834 @@
           throw MOADNSException(e.what()); // translate
         }
+        if(MT->numProcesses() > g_maxMThreads) {
+          g_stats.overCapacityDrops++;
+          return;
+        }
+  
         DNSComboWriter* dc = new DNSComboWriter(data, len, g_now);
         dc->setSocket(fd);
@@ -1529 +1543 @@
   L<<Logger::Warning<<"Operating in "<<(sizeof(unsigned long)*8) <<" bits mode"<<endl;
   
+  #if 0
+  unsigned int maxFDs, curFDs;
+  getFDLimits(curFDs, maxFDs);
+  if(curFDs < 2048) 
+    L<<Logger::Warning<<"Only "<<curFDs<<" file descriptors available (out of: "<<maxFDs<<"), may not be suitable for high performance"<<endl;
+  #endif
+  
   seedRandom(::arg()["entropy-source"]);
 
@@ -1632 +1653 @@
   g_tcpTimeout=::arg().asNum("client-tcp-timeout");
   g_maxTCPPerClient=::arg().asNum("max-tcp-per-client");
+  g_maxMThreads=::arg().asNum("max-mthreads");
   
   int numThreads = ::arg().asNum("threads");
@@ -1855 +1877 @@
     ::arg().set("query-local-address6","Source IPv6 address for sending queries")="";
     ::arg().set("client-tcp-timeout","Timeout in seconds when talking to TCP clients")="2";
+    ::arg().set("max-mthreads", "Maximum number of simultaneous Mtasker threads")="2048";
     ::arg().set("max-tcp-clients","Maximum number of simultaneous TCP clients")="128";
     ::arg().set("hint-file", "If set, load root hints from this file")="";

trunk/pdns/pdns/syncres.hh

@@ -472 +472 @@
   uint64_t spoofCount;
   uint64_t resourceLimits;
+  uint64_t overCapacityDrops;
   uint64_t ipv6queries;
   uint64_t chainResends;