Faster timeouts, based on extracts of our logs.

git-svn-id: file:///svn/unbound/trunk@689 be551aaa-1e26-0410-a405-d3ace91eadb9

doc/Changelog

@@ -15,6 +15,8 @@
 	  where no scripted answer was available.
 	- mark insecure RRs as insecure.
 	- fixup removal of nonsecure items from the additional.
+	- reduced timeout values to more realistic, 376 msec (262 msec has
+	  90% of roundtrip times, 512 msec has 99% of roundtrip times.)
 
 16 October 2007: Wouter
 	- no malloc in log_hex.

iterator/iterator.h

@@ -58,7 +58,7 @@ struct iter_prep_list;
 /** how nice is a server without further information, in msec 
  * Equals rtt initial timeout value.
  */
-#define UNKNOWN_SERVER_NICENESS 3000
+#define UNKNOWN_SERVER_NICENESS 376
 /** maximum timeout before a host is deemed unsuitable, in msec. 
  * After host_ttl this will be timed out and the host will be tried again. 
  * Equals RTT_MAX_TIMEOUT

util/rtt.c

@@ -60,9 +60,10 @@ void
 rtt_init(struct rtt_info* rtt)
 {
 	rtt->srtt = 0;
-	rtt->rttvar = 750;
+	rtt->rttvar = 94;
 	rtt->rto = calc_rto(rtt);
-	/* first RTO is 0 + 4*0.75 = 3 seconds */
+	/* default value from the book is 0 + 4*0.75 = 3 seconds */
+	/* first RTO is 0 + 4*0.094 = 0.376 seconds */
 }
 
 int 

util/rtt.h

@@ -56,7 +56,7 @@ struct rtt_info {
 };
 
 /** min retransmit timeout value, in milliseconds */
-#define RTT_MIN_TIMEOUT	2000
+#define RTT_MIN_TIMEOUT	50
 /** max retransmit timeout value, in milliseconds */
 #define RTT_MAX_TIMEOUT 120000