Changeset 931

Timestamp:

12/16/06 16:04:10 (2 years ago)

Author:

ahu

Message:

implement rest of speedups + some debugging output + i386 specific code (sorry)

Files:

• trunk/pdns/pdns/misc.hh (modified) (1 diff)
• trunk/pdns/pdns/pdns_recursor.cc (modified) (14 diffs)
• trunk/pdns/pdns/recursor_cache.cc (modified) (1 diff)
• trunk/pdns/pdns/recursor_cache.hh (modified) (2 diffs)
• trunk/pdns/pdns/syncres.hh (modified) (1 diff)

trunk/pdns/pdns/misc.hh

@@ -20 +20 @@
-#define MISC_HH
-
-0
+1
-#define RDTSC(qp) \
-do { \

trunk/pdns/pdns/pdns_recursor.cc

@@ -283 +283 @@
-    --d_numsocks;
-  }
-
+ 
-
-
@@ -395 +395 @@
-  setBuffer(fd, SO_SNDBUF, size);
-}
+
-
-static void writePid(void)
@@ -486 +487 @@
-{
-  DNSComboWriter* dc=(DNSComboWriter *)p;
+
-  try {
-    uint16_t maxudpsize=512;
@@ -494 +496 @@
-    
-    vector<DNSResourceRecord> ret;
-    
-    vector<uint8_t> packet;
-
+
+
-
-    pw.getHeader()->aa=0;
@@ -514 +516 @@
-
-    int res=sr.beginResolve(dc->d_mdp.d_qname, QType(dc->d_mdp.d_qtype), dc->d_mdp.d_qclass, ret);
+
-    if(res<0) {
-      pw.getHeader()->rcode=RCode::ServFail;
@@ -535 +538 @@
-      if(ret.size()) {
-        shuffle(ret);
-
-  pw.startRecord(i->qname, i->qtype.getCode(), i->ttl, i->qclass, (DNSPacketWriter::Place)i->d_place);
-shared_ptr<DNSRecordContent> drc(DNSRecordContent::mastermake(i->qtype.getCode(), i->qclass, i->content));
+
+for(vector<DNSResourceRecord>::const_iterator i=ret.begin(); i!=ret.end(); ++i) {
+pw.startRecord(i->qname, i->qtype.getCode(), i->ttl, i->qclass, (DNSPacketWriter::Place)i->d_place); 
-          
-
-
+
+
+
+
+
+
+
+
-          if(!dc->d_tcp && pw.size() > maxudpsize) {
-            pw.rollback();
@@ -548 +557 @@
-          }
-        }
+
-        pw.commit();
-      }
@@ -594 +604 @@
-      }
-    }
-
+
-    if(!g_quiet) {
-      L<<Logger::Error<<"["<<MT->getTid()<<"] answer to "<<(dc->d_mdp.d_header.rd?"":"non-rd ")<<"question '"<<dc->d_mdp.d_qname<<"|"<<DNSRecordContent::NumberToType(dc->d_mdp.d_qtype);
@@ -600 +610 @@
-        sr.d_throttledqueries<<" throttled, "<<sr.d_timeouts<<" timeouts, "<<sr.d_tcpoutqueries<<" tcp connections, rcode="<<res<<endl;
-    }
-
+
-    sr.d_outqueries ? RC.cacheMisses++ : RC.cacheHits++; 
-    float spent=makeFloat(sr.d_now-dc->d_now);
@@ -617 +627 @@
-    if(newLat < 1000000)  // outliers of several minutes exist..
-      g_stats.avgLatencyUsec=(uint64_t)((1-0.0001)*g_stats.avgLatencyUsec + 0.0001*newLat);
+
-    delete dc;
-  }
@@ -765 +776 @@
-}
- 
+void questionExpand(const char* packet, uint16_t len, char* qname, int maxlen, uint16_t& type)
+{
+  type=0;
+  const unsigned char* end=(const unsigned char*)packet+len;
+  unsigned char* lbegin=(unsigned char*)packet+12;
+  unsigned char* pos=lbegin;
+  unsigned char labellen;
+
+  // 3www4ds9a2nl0
+  char *dst=qname;
+  char* lend=dst + maxlen;
+  
+  if(!*pos)
+    *dst++='.';
+
+  while((labellen=*pos++) && pos < end) { // "scan and copy"
+    if(dst >= lend)
+      throw runtime_error("Label length exceeded destination length");
+    for(;labellen;--labellen)
+      *dst++ = *pos++;
+    *dst++='.';
+  }
+  *dst=0;
+
+  if(pos + labellen + 2 <= end)  // is this correct XXX FIXME?
+    type=(*pos)*256 + *(pos+1);
+
+
+  //  cerr<<"Returning: '"<< string(tmp+1, pos) <<"'\n";
+}
+
+string questionExpand(const char* packet, uint16_t len, uint16_t& type)
+{
+  char tmp[512];
+  questionExpand(packet, len, tmp, sizeof(tmp), type);
+  return tmp;
+}
+
-void handleNewUDPQuestion(int fd, boost::any& var)
-{
@@ -771 +820 @@
-  ComboAddress fromaddr;
-  socklen_t addrlen=sizeof(fromaddr);
+  uint64_t tsc1, tsc2;
-
-  if((len=recvfrom(fd, data, sizeof(data), 0, (sockaddr *)&fromaddr, &addrlen)) >= 0) {
+    RDTSC(tsc1);      
-    g_stats.addRemote(fromaddr);
+
-    if(g_allowFrom && !g_allowFrom->match(&fromaddr)) {
-      if(!g_quiet) 
@@ -782 +834 @@
-    }
-    try {
-
-
+
-      
-c->d_mdp.d_header.
+h->
-        if(g_logCommonErrors)
-
-
+
-      }
-      else {
-        ++g_stats.qcounter;
+        uint16_t type;
+        char qname[256];
+        questionExpand(data, len, qname, sizeof(qname), type);  
+        
+        // must all be same length answers right now!
+        if((type==QType::A || type==QType::AAAA) && dh->arcount==0 && dh->ancount==0 && dh->nscount ==0 && ntohs(dh->qdcount)==1 ) {
+          char *record[10];
+          uint16_t rlen[10];
+          uint32_t ttd[10];
+          int count;
+          if((count=RC.getDirect(g_now.tv_sec, qname, QType(type), ttd, record, rlen))) { 
+            if(len + count*(sizeof(dnsrecordheader) + 2 + rlen[0]) > 512)
+              goto slow;
+
+            random_shuffle(record, &record[count]);
+            dh->qr=1;
+            dh->ra=1;
+            dh->ancount=ntohs(count);
+            for(int n=0; n < count ; ++n) {
+              memcpy(data+len, "\xc0\x0c", 2); // answer label pointer
+              len+=2;
+              struct dnsrecordheader drh;
+              drh.d_type=htons(type);
+              drh.d_class=htons(1);
+              drh.d_ttl=htonl(ttd[n] - g_now.tv_sec);
+              drh.d_clen=htons(rlen[n]);
+              memcpy(data+len, &drh, sizeof(drh));
+              len+=sizeof(drh);
+              memcpy(data+len, record[n], rlen[n]);
+              len+=rlen[n];
+            }
+            RDTSC(tsc2);            
+            g_stats.shunted++;
+            sendto(fd, data, len, 0, (struct sockaddr *)(&fromaddr), fromaddr.getSocklen());
+            cerr<<"shunted: " << (tsc2-tsc1) / 3000.0 << endl;
+            return;
+          }
+        }
+      slow:
+        DNSComboWriter* dc = new DNSComboWriter(data, len, g_now);
-        dc->setSocket(fd);
+        dc->setRemote(&fromaddr);
+
-        dc->d_tcp=false;
+
-        MT->makeThread(startDoResolve, (void*) dc); // deletes dc
-      }
@@ -1028 +1121 @@
-}
-;
-
-string questionExpand(const char* packet, uint16_t len, uint16_t& type)
-{
-  type=0;
-  const unsigned char* end=(const unsigned char*)packet+len;
-  const unsigned char* pos=(const unsigned char*)packet+12;
-  unsigned char labellen;
-  string ret;
-  ret.reserve(len-12);
-  while((labellen=*pos++)) {
-    if(pos+labellen > end)
-      break;
-    ret.append((const char*)pos, labellen);
-    ret.append(1,'.');
-    pos+=labellen;
-  }
-  if(ret.empty())
-    ret=".";
-
-  if(pos + labellen + 2 <= end)  // is this correct XXX FIXME?
-    type=(*pos)*256 + *(pos+1);
-    
-  return ret;
-}
-
-

trunk/pdns/pdns/recursor_cache.cc

@@ -143 +143 @@
-}
-
+int MemRecursorCache::getDirect(time_t now, const char* qname, const QType& qt, uint32_t ttd[10], char* data[10], uint16_t len[10])
+{
+  if(!d_cachecachevalid || Utility::strcasecmp(d_cachedqname.c_str(), qname)) {
+    cerr<<"had cache cache miss for '"<<qname<<"'"<<endl;
+    d_cachedqname=qname;
+    d_cachecache=d_cache.equal_range(tie(qname));
+    d_cachecachevalid=true;
+  }
+  else
+    ;
+  //    cerr<<"had cache cache hit!"<<endl;
+
+  if(d_cachecache.first == d_cachecache.second)
+    return false;
+
+  pair<cache_t::iterator, cache_t::iterator> range = d_cachecache;
+  
+  unsigned int n=0;
+  for(;range.first != range.second; ++range.first) {
+    if(range.first->d_qtype == QType::CNAME) // if we see a cname, we need the whole shebang (for now)
+      return false;
+    if(range.first->d_qtype != qt.getCode())
+      continue;
+    if(range.first->getTTD() < (unsigned int) now)
+      return false;
+    
+    if(range.first->d_records.empty() || range.first->d_records.size() > 9 )
+      return false;
+    
+    size_t limit=range.first->d_records.size();
+    n=0;
+    for(; n < limit; ++n) {
+      data[n]=(char*)range.first->d_records[n].d_string.c_str();
+      len[n]=range.first->d_records[n].d_string.length();
+      ttd[n]=range.first->d_records[n].d_ttd;
+    }
+    if(n<10) {
+      data[n]=0;
+      typedef cache_t::nth_index<1>::type sequence_t;
+      sequence_t& sidx=d_cache.get<1>();
+      sequence_t::iterator si=d_cache.project<1>(range.first);
+      sidx.relocate(sidx.end(), si); // move it in the LRU list 
+      // can't yet return, need to figure out if there isn't a CNAME that messes things up
+    }
+    else
+      return false;
+  }
+  return n;
+
+}
-
-int MemRecursorCache::get(time_t now, const string &qname, const QType& qt, set<DNSResourceRecord>* res)

trunk/pdns/pdns/recursor_cache.hh

@@ -33 +33 @@
-  unsigned int bytes();
-  int get(time_t, const string &qname, const QType& qt, set<DNSResourceRecord>* res);
+
+  int getDirect(time_t now, const char* qname, const QType& qt, uint32_t ttd[10], char* data[10], uint16_t len[10]);
-  void replace(time_t, const string &qname, const QType& qt,  const set<DNSResourceRecord>& content, bool auth);
-  void doPrune(void);
@@ -96 +98 @@
-      return earliest;
-    }
-
-  };
-

trunk/pdns/pdns/syncres.hh

@@ -478 +478 @@
-  uint64_t chainResends;
-  uint64_t nsSetInvalidations;
+  uint64_t shunted;
-
-  typedef vector<ComboAddress> remotes_t;