--- gvpe/src/vpn_dns.C	2005/03/07 01:31:26	1.24
+++ gvpe/src/vpn_dns.C	2005/03/13 12:33:34	1.28
@@ -54,13 +54,14 @@
 #define INITIAL_SYN_TIMEOUT 10. // retry timeout for initial syn
 
 #define MIN_SEND_INTERVAL 0.01 // wait at least this time between sending requests
-#define MAX_SEND_INTERVAL 0.5 // optimistic?
+#define MAX_SEND_INTERVAL 2. // optimistic?
 
-#define MAX_OUTSTANDING 10 // max. outstanding requests
+#define LATENCY_FACTOR   0.5 // RTT * LATENCY_FACTOR == sending rate
+#define MAX_OUTSTANDING  100 // max. outstanding requests
 #define MAX_WINDOW      1000 // max. for MAX_OUTSTANDING, and backlog
 #define MAX_BACKLOG     (100*1024) // size of gvpe protocol backlog (bytes), must be > MAXSIZE
 
-#define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well
+#define MAX_DOMAIN_SIZE 240 // 255 is legal limit, but bind doesn't compress well
 // 240 leaves about 4 bytes of server reply data
 // every two request bytes less give room for one reply byte
 
@@ -450,8 +451,8 @@
   seq_cdc  = 26;
   req_cdc  = 62;
   rep_cdc  = 0;
-  max_size = ntohs (MAX_PKT_SIZE);
-  client   = ntohs (clientid);
+  max_size = htons (MAX_PKT_SIZE);
+  client   = htons (clientid);
   uid      = next_uid++;
 
   r2 = r3 = r4 = 0;
@@ -467,8 +468,7 @@
       && seq_cdc == 26
       && req_cdc == 62
       && rep_cdc == 0
-      && version == 1
-      && max_size == ntohs (MAX_PKT_SIZE);
+      && version == 1;
 }
 
 struct dns_packet : net_packet
@@ -549,7 +549,7 @@
 
   tstamp last_received;
   tstamp last_sent;
-  double last_latency;
+  double min_latency;
   double poll_interval, send_interval;
 
   vector<dns_rcv *> rcvpq;
@@ -733,7 +733,7 @@
   last_sent = last_received = 0;
   poll_interval = MIN_POLL_INTERVAL;
   send_interval = 0.5; // starting rate
-  last_latency = INITIAL_TIMEOUT;
+  min_latency = INITIAL_TIMEOUT;
 }
 
 dns_connection::~dns_connection ()
@@ -756,6 +756,7 @@
   else
     {
       poll_interval *= 1.5;
+
       if (poll_interval > MAX_POLL_INTERVAL)
         poll_interval = MAX_POLL_INTERVAL;
     }
@@ -894,12 +895,13 @@
 
                     int rdlen_offs = offs += 2;
 
-                    int dlen = (dns ? ntohs (dns->cfg.max_size) : MAX_PKT_SIZE) - offs;
-                    // bind doesn't compress well, so reduce further by one label length
-                    dlen -= qlen;
-
                     if (dns)
                       {
+                        int dlen = ntohs (dns->cfg.max_size) - offs;
+
+                        // bind doesn't compress well, so reduce further by one label length
+                        dlen -= qlen;
+
                         // only put data into in-order sequence packets, if
                         // we receive out-of-order packets we generate empty
                         // replies
@@ -1017,19 +1019,21 @@
           }
         else
           {
-#if 1
+#if 0
             dns->send_interval *= 0.999;
 #endif
-            if (dns->send_interval < MIN_SEND_INTERVAL)
-              dns->send_interval = MIN_SEND_INTERVAL;
-
             // the latency surely puts an upper bound on
             // the minimum send interval
             double latency = NOW - (*i)->sent;
-            dns->last_latency = latency;
 
-            if (dns->send_interval > latency)
-              dns->send_interval = latency;
+            if (latency < dns->min_latency)
+              dns->min_latency = latency;
+
+            if (dns->send_interval > dns->min_latency * LATENCY_FACTOR)
+              dns->send_interval = dns->min_latency * LATENCY_FACTOR;
+
+            if (dns->send_interval < MIN_SEND_INTERVAL)
+              dns->send_interval = MIN_SEND_INTERVAL;
           }
 
         delete *i;
@@ -1221,13 +1225,13 @@
               send = r;
 
               r->retry++;
-              r->timeout = NOW + (r->retry * last_latency * 8.);
+              r->timeout = NOW + (r->retry * min_latency * 8.);
 
               // the following code changes the query section a bit, forcing
               // the forwarder to generate a new request
               if (r->stdhdr)
                 {
-                  //printf ("reencoded header for ID %d retry %d:%d:%d\n", htons (r->pkt->id), THISNODE->id, r->seqno, r->retry);printf ("reencoded header for ID %d retry %d:%d:%d\n", htons (r->pkt->id), THISNODE->id, r->seqno, r->retry);
+                  //printf ("reencoded header for ID %d retry %d:%d:%d (%p)\n", htons (r->pkt->id), THISNODE->id, r->seqno, r->retry);
                   //encode_header ((char *)r->pkt->at (6 * 2 + 1), THISNODE->id, r->seqno, r->retry);
                 }
             }
@@ -1236,9 +1240,9 @@
         NEXT (r->timeout);
     }
 
-  if (last_sent + send_interval <= NOW)
+  if (!send)
     {
-      if (!send)
+      if (last_sent + send_interval <= NOW)
         {
           // generate a new packet, if wise
 
@@ -1256,7 +1260,7 @@
                    && !SEQNO_EQ (rcvseq, sndseq - (MAX_WINDOW - 1)))
             {
               //printf ("sending data request etc.\n"); //D
-              if (!snddq.empty ())
+              if (!snddq.empty () || last_received + 1. > NOW)
                 {
                   poll_interval = send_interval;
                   NEXT (NOW + send_interval);
@@ -1264,7 +1268,7 @@
 
               send = new dns_snd (this);
               send->gen_stream_req (sndseq, snddq);
-              send->timeout = NOW + last_latency * 8.;
+              send->timeout = NOW + min_latency * 8.;
 
               sndseq = (sndseq + 1) & SEQNO_MASK;
             }
@@ -1272,21 +1276,22 @@
           if (send)
             vpn->dns_sndpq.push_back (send);
         }
+      else
+        NEXT (last_sent + send_interval);
+    }
 
-      if (send)
-        {
-          last_sent = NOW;
-          sendto (vpn->dnsv4_fd,
-                  send->pkt->at (0), send->pkt->len, 0,
-                  vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
-        }
+  if (send)
+    {
+      last_sent = NOW;
+      sendto (vpn->dnsv4_fd,
+              send->pkt->at (0), send->pkt->len, 0,
+              vpn->dns_forwarder.sav4 (), vpn->dns_forwarder.salenv4 ());
     }
-  else
-    NEXT (last_sent + send_interval);
 
-  slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d)",
+  slog (L_NOISE, "DNS: pi %f si %f N %f (%d:%d %d)",
         poll_interval, send_interval, next - NOW,
-        vpn->dns_sndpq.size (), snddq.size ());
+        vpn->dns_sndpq.size (), snddq.size (),
+        rcvpq.size ());
 
   // TODO: no idea when this happens, but when next < NOW, we have a problem
   if (next < NOW + 0.0001)