Make rbtdb maintain stale counters

When updating the statistics for RRset types, if a header is marked
stale or ancient, the appropriate statistic counters are decremented,
then incremented.

Also fix some out of date comments.

bin/tests/system/serve-stale/clean.sh

@@ -15,3 +15,4 @@ rm -f rndc.out.test*
 rm -f */named.run */named.memstats
 rm -f ns*/managed-keys.bind*
 rm -f ns*/named_dump*
+rm -f ns*/named.stats*

bin/tests/system/serve-stale/ns1/named2.conf.in

@@ -27,7 +27,7 @@ options {
 	listen-on { 10.53.0.1; };
 	listen-on-v6 { none; };
 	recursion yes;
-	max-stale-ttl 7200;
+	max-stale-ttl 35;
 	stale-answer-ttl 3;
 	stale-answer-enable yes;
 };

bin/tests/system/serve-stale/tests.sh

@@ -31,6 +31,11 @@ n=0
 #$DIG -p ${PORT} @10.53.0.2 nodata.example TXT
 #$DIG -p ${PORT} @10.53.0.2 nxdomain.example TXT
 
+#
+# First test server with serve-stale options set.
+#
+echo_i "test server with serve-stale options set"
+
 n=`expr $n + 1`
 echo_i "prime cache longttl.example ($n)"
 ret=0
@@ -67,6 +72,22 @@ grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+n=`expr $n + 1`
+echo_i "verify prime cache statistics ($n)"
+ret=0
+rm -f ns1/named.stats
+$RNDCCMD 10.53.0.1 stats > /dev/null 2>&1
+[ -f ns1/named.stats ] || ret=1
+cp ns1/named.stats ns1/named.stats.$n
+# Check first 10 lines of Cache DB statistics.  After prime queries, we expect
+# two active TXT one nxrrset TXT, and one NXDOMAIN.
+grep -A 10 "++ Cache DB RRsets ++" ns1/named.stats.$n > ns1/named.stats.$n.cachedb || ret=1
+grep "2 TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 !TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 NXDOMAIN" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
 n=`expr $n + 1`
 echo_i "disable responses from authoritative server ($n)"
 ret=0
@@ -125,6 +146,24 @@ grep "example\..*2.*IN.*SOA" dig.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+n=`expr $n + 1`
+echo_i "verify stale cache statistics ($n)"
+ret=0
+rm -f ns1/named.stats
+$RNDCCMD 10.53.0.1 stats > /dev/null 2>&1
+[ -f ns1/named.stats ] || ret=1
+cp ns1/named.stats ns1/named.stats.$n
+# Check first 10 lines of Cache DB statistics.  After serve-stale queries, we
+# expect one active TXT RRset, one stale TXT, one stale nxrrset TXT, and one
+# stale NXDOMAIN.
+grep -A 10 "++ Cache DB RRsets ++" ns1/named.stats.$n > ns1/named.stats.$n.cachedb || ret=1
+grep "1 TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #!TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #NXDOMAIN" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+status=`expr $status + $ret`
+if [ $ret != 0 ]; then echo_i "failed"; fi
+
 n=`expr $n + 1`
 echo_i "running 'rndc serve-stale off' ($n)"
 ret=0
@@ -362,6 +401,12 @@ grep '_default: off (rndc) (stale-answer-ttl=2 max-stale-ttl=3600)' rndc.out.tes
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+#
+# Update named.conf.
+# Test server with low max-stale-ttl.
+#
+echo_i "test server with serve-stale options set, low max-stale-ttl"
+
 n=`expr $n + 1`
 echo_i "updating ns1/named.conf ($n)"
 ret=0
@@ -380,23 +425,7 @@ n=`expr $n + 1`
 echo_i "check 'rndc serve-stale status' ($n)"
 ret=0
 $RNDCCMD 10.53.0.1 serve-stale status > rndc.out.test$n 2>&1 || ret=1
-grep '_default: off (rndc) (stale-answer-ttl=3 max-stale-ttl=7200)' rndc.out.test$n > /dev/null || ret=1
+grep '_default: off (rndc) (stale-answer-ttl=3 max-stale-ttl=35)' rndc.out.test$n > /dev/null || ret=1
-if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
-
-n=`expr $n + 1`
-echo_i "check 'rndc serve-stale' ($n)"
-ret=0
-$RNDCCMD 10.53.0.1 serve-stale > rndc.out.test$n 2>&1 && ret=1
-grep "unexpected end of input" rndc.out.test$n > /dev/null || ret=1
-if [ $ret != 0 ]; then echo_i "failed"; fi
-status=`expr $status + $ret`
-
-n=`expr $n + 1`
-echo_i "check 'rndc serve-stale unknown' ($n)"
-ret=0
-$RNDCCMD 10.53.0.1 serve-stale unknown > rndc.out.test$n 2>&1 && ret=1
-grep "syntax error" rndc.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
@@ -411,6 +440,14 @@ grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+n=`expr $n + 1`
+echo_i "check 'rndc serve-stale status' ($n)"
+ret=0
+$RNDCCMD 10.53.0.1 serve-stale status > rndc.out.test$n 2>&1 || ret=1
+grep '_default: on (rndc) (stale-answer-ttl=3 max-stale-ttl=35)' rndc.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
 n=`expr $n + 1`
 echo_i "enable responses from authoritative server ($n)"
 ret=0
@@ -420,6 +457,171 @@ grep "TXT.\"1\"" dig.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+sleep 1
+
+n=`expr $n + 1`
+echo_i "prime cache longttl.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 longttl.example TXT > dig.out.test$n
+grep "status: NOERROR" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 1," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "prime cache data.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 data.example TXT > dig.out.test$n
+grep "status: NOERROR" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 1," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "prime cache nodata.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 nodata.example TXT > dig.out.test$n
+grep "status: NOERROR" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "prime cache nxdomain.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 nxdomain.example TXT > dig.out.test$n
+grep "status: NXDOMAIN" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "verify prime cache statistics (low max-stale-ttl) ($n)"
+ret=0
+rm -f ns1/named.stats
+$RNDCCMD 10.53.0.1 stats > /dev/null 2>&1
+[ -f ns1/named.stats ] || ret=1
+cp ns1/named.stats ns1/named.stats.$n
+# Check first 10 lines of Cache DB statistics.  After prime queries, we expect
+# two active TXT RRsets, one nxrrset TXT, and one NXDOMAIN.
+grep -A 10 "++ Cache DB RRsets ++" ns1/named.stats.$n > ns1/named.stats.$n.cachedb || ret=1
+grep "2 TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 !TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 NXDOMAIN" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+status=`expr $status + $ret`
+if [ $ret != 0 ]; then echo_i "failed"; fi
+
+n=`expr $n + 1`
+echo_i "disable responses from authoritative server ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.2 txt disable  > dig.out.test$n
+grep "ANSWER: 1," dig.out.test$n > /dev/null || ret=1
+grep "TXT.\"0\"" dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+sleep 1
+
+n=`expr $n + 1`
+echo_i "check stale data.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 data.example TXT > dig.out.test$n
+grep "status: NOERROR" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 1," dig.out.test$n > /dev/null || ret=1
+grep "data\.example\..*3.*IN.*TXT.*A text record with a 1 second ttl" dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "check stale nodata.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 nodata.example TXT > dig.out.test$n
+grep "status: NOERROR" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+grep "example\..*3.*IN.*SOA" dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "check stale nxdomain.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 nxdomain.example TXT > dig.out.test$n
+grep "status: NXDOMAIN" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+grep "example\..*3.*IN.*SOA" dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "verify stale cache statistics (low max-stale-ttl) ($n)"
+ret=0
+rm -f ns1/named.stats
+$RNDCCMD 10.53.0.1 stats > /dev/null 2>&1
+[ -f ns1/named.stats ] || ret=1
+cp ns1/named.stats ns1/named.stats.$n
+# Check first 10 lines of Cache DB statistics.  After serve-stale queries, we
+# expect one active TXT RRset, one stale TXT, one stale nxrrset TXT, and one
+# stale NXDOMAIN.
+grep -A 10 "++ Cache DB RRsets ++" ns1/named.stats.$n > ns1/named.stats.$n.cachedb || ret=1
+grep "1 TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #!TXT" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #NXDOMAIN" ns1/named.stats.$n.cachedb > /dev/null || ret=1
+status=`expr $status + $ret`
+if [ $ret != 0 ]; then echo_i "failed"; fi
+
+sleep 1
+
+n=`expr $n + 1`
+echo_i "check ancient data.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 data.example TXT > dig.out.test$n
+grep "status: SERVFAIL" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "check ancient nodata.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 nodata.example TXT > dig.out.test$n
+grep "status: SERVFAIL" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "check ancient nxdomain.example (low max-stale-ttl) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.1 nxdomain.example TXT > dig.out.test$n
+grep "status: SERVFAIL" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+#
+# Now test server with no serve-stale options set.
+#
+echo_i "test server with no serve-stale options set"
+
+n=`expr $n + 1`
+echo_i "enable responses from authoritative server ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.2 txt enable  > dig.out.test$n
+grep "ANSWER: 1," dig.out.test$n > /dev/null || ret=1
+grep "TXT.\"1\"" dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
+n=`expr $n + 1`
+echo_i "prime cache longttl.example (max-stale-ttl default) ($n)"
+ret=0
+$DIG -p ${PORT} @10.53.0.3 longttl.example TXT > dig.out.test$n
+grep "status: NOERROR" dig.out.test$n > /dev/null || ret=1
+grep "ANSWER: 1," dig.out.test$n > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
 n=`expr $n + 1`
 echo_i "prime cache data.example (max-stale-ttl default) ($n)"
 ret=0
@@ -459,6 +661,22 @@ grep "TXT.\"0\"" dig.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+n=`expr $n + 1`
+echo_i "verify prime cache statistics (max-stale-ttl default) ($n)"
+ret=0
+rm -f ns3/named.stats
+$RNDCCMD 10.53.0.3 stats > /dev/null 2>&1
+[ -f ns3/named.stats ] || ret=1
+cp ns3/named.stats ns3/named.stats.$n
+# Check first 10 lines of Cache DB statistics.  After prime queries, we expect
+# two active TXT RRsets, one nxrrset TXT, and one NXDOMAIN.
+grep -A 10 "++ Cache DB RRsets ++" ns3/named.stats.$n > ns3/named.stats.$n.cachedb || ret=1
+grep "2 TXT" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 !TXT" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 NXDOMAIN" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+status=`expr $status + $ret`
+if [ $ret != 0 ]; then echo_i "failed"; fi
+
 sleep 1
 
 n=`expr $n + 1`
@@ -496,6 +714,24 @@ grep "ANSWER: 0," dig.out.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+n=`expr $n + 1`
+echo_i "verify stale cache statistics (max-stale-ttl default) ($n)"
+ret=0
+rm -f ns3/named.stats
+$RNDCCMD 10.53.0.3 stats > /dev/null 2>&1
+[ -f ns3/named.stats ] || ret=1
+cp ns3/named.stats ns3/named.stats.$n
+# Check first 10 lines of Cache DB statistics. After last queries, we expect
+# one active TXT RRset, one stale TXT, one stale nxrrset TXT, and one
+# stale NXDOMAIN.
+grep -A 10 "++ Cache DB RRsets ++" ns3/named.stats.$n > ns3/named.stats.$n.cachedb || ret=1
+grep "1 TXT" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #TXT" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #!TXT" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+grep "1 #NXDOMAIN" ns3/named.stats.$n.cachedb > /dev/null || ret=1
+status=`expr $status + $ret`
+if [ $ret != 0 ]; then echo_i "failed"; fi
+
 n=`expr $n + 1`
 echo_i "check 'rndc serve-stale on' ($n)"
 ret=0

lib/dns/rbtdb.c

@@ -194,7 +194,7 @@ typedef struct rdatasetheader {
 	rbtdb_serial_t                  serial;
 	dns_ttl_t                       rdh_ttl;
 	rbtdb_rdatatype_t               type;
-	uint16_t                    attributes;
+	uint16_t                        attributes;
 	dns_trust_t                     trust;
 	struct noqname                  *noqname;
 	struct noqname                  *closest;
@@ -831,17 +831,23 @@ update_rrsetstats(dns_rbtdb_t *rbtdb, rdatasetheader_t *header,
 			statattributes = DNS_RDATASTATSTYPE_ATTR_NXRRSET;
 			base = RBTDB_RDATATYPE_EXT(header->type);
 		}
-	} else
+	} else {
 		base = RBTDB_RDATATYPE_BASE(header->type);
+	}
 
-	if (STALE(header))
+	if (STALE(header)) {
 		statattributes |= DNS_RDATASTATSTYPE_ATTR_STALE;
+	}
+	if (ANCIENT(header)) {
+		statattributes |= DNS_RDATASTATSTYPE_ATTR_ANCIENT;
+	}
 
 	type = DNS_RDATASTATSTYPE_VALUE(base, statattributes);
-	if (increment)
+	if (increment) {
 		dns_rdatasetstats_increment(rbtdb->rrsetstats, type);
-	else
+	} else {
 		dns_rdatasetstats_decrement(rbtdb->rrsetstats, type);
+	}
 }
 
 static void
@@ -1507,24 +1513,68 @@ rollback_node(dns_rbtnode_t *node, rbtdb_serial_t serial) {
 
 static inline void
 mark_header_ancient(dns_rbtdb_t *rbtdb, rdatasetheader_t *header) {
+	bool do_stats = false;
 
 	/*
 	 * If we are already ancient there is nothing to do.
 	 */
-	if (ANCIENT(header))
+	if (ANCIENT(header)) {
 		return;
+	}
+
+	if ((header->attributes & RDATASET_ATTR_STATCOUNT) != 0) {
+		do_stats = EXISTS(header);
+	}
+
+	if (do_stats) {
+		/*
+		 * Decrement the stats counter for the appropriate RRtype.
+		 * If the STALE attribute is set, this will decrement the
+		 * stale type counter, otherwise it decrements the active
+		 * stats type counter.
+		 */
+		update_rrsetstats(rbtdb, header, false);
+	}
 
 	header->attributes |= RDATASET_ATTR_ANCIENT;
 	header->node->dirty = 1;
 
-	/*
+	if (do_stats) {
-	 * If we have not been counted then there is nothing to do.
+		/* Increment the stats counter for the ancient RRtype. */
-	 */
-	if ((header->attributes & RDATASET_ATTR_STATCOUNT) == 0)
-		return;
-
-	if (EXISTS(header))
 		update_rrsetstats(rbtdb, header, true);
+	}
+}
+
+static inline void
+mark_header_stale(dns_rbtdb_t *rbtdb, rdatasetheader_t *header) {
+	bool do_stats = false;
+
+	/*
+	 * If we are already stale there is nothing to do.
+	 */
+	if (STALE(header)) {
+		return;
+	}
+
+	if ((header->attributes & RDATASET_ATTR_STATCOUNT) != 0) {
+		do_stats = EXISTS(header);
+	}
+
+	if (do_stats) {
+		/* Decrement the stats counter for the appropriate RRtype.
+		 * If the ANCIENT attribute is set (although it is very
+		 * unlikely that an RRset goes from ANCIENT to STALE), this
+		 * will decrement the ancient stale type counter, otherwise it
+		 * decrements the active stats type counter.
+		 */
+		update_rrsetstats(rbtdb, header, false);
+	}
+
+	header->attributes |= RDATASET_ATTR_STALE;
+
+	if (do_stats) {
+		update_rrsetstats(rbtdb, header, true);
+	}
 }
 
 static inline void
@@ -4320,7 +4370,7 @@ check_stale_header(dns_rbtnode_t *node, rdatasetheader_t *header,
 		 * skip this record.
 		 */
 		if (KEEPSTALE(search->rbtdb) && stale > search->now) {
-			header->attributes |= RDATASET_ATTR_STALE;
+			mark_header_stale(search->rbtdb, header);
 			*header_prev = header;
 			return ((search->options & DNS_DBFIND_STALEOK) == 0);
 		}
@@ -4328,7 +4378,7 @@ check_stale_header(dns_rbtnode_t *node, rdatasetheader_t *header,
 		/*
 		 * This rdataset is stale.  If no one else is using the
 		 * node, we can clean it up right now, otherwise we mark
-		 * it as stale, and the node as dirty, so it will get
+		 * it as ancient, and the node as dirty, so it will get
 		 * cleaned up later.
 		 */
 		if ((header->rdh_ttl < search->now - RBTDB_VIRTUAL) &&
@@ -5289,7 +5339,8 @@ expirenode(dns_db_t *db, dns_dbnode_t *node, isc_stdtime_t now) {
 			mark_header_ancient(rbtdb, header);
 			if (log)
 				isc_log_write(dns_lctx, category, module,
-					      level, "overmem cache: stale %s",
+					      level,
+					      "overmem cache: ancient %s",
 					      printname);
 		} else if (force_expire) {
 			if (! RETAIN(header)) {
@@ -5824,7 +5875,7 @@ add32(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
 				 * which covers all types (NXDOMAIN,
 				 * NODATA(QTYPE=ANY)),
 				 *
-				 * We make all other data stale so that the
+				 * We make all other data ancient so that the
 				 * only rdataset that can be found at this
 				 * node is the negative cache entry.
 				 */
@@ -5839,7 +5890,7 @@ add32(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
 			}
 			/*
 			 * Otherwise look for any RRSIGs of the given
-			 * type so they can be marked stale later.
+			 * type so they can be marked ancient later.
 			 */
 			for (topheader = rbtnode->data;
 			     topheader != NULL;
@@ -5851,9 +5902,9 @@ add32(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
 			/*
 			 * We're adding something that isn't a
 			 * negative cache entry.  Look for an extant
-			 * non-stale NXDOMAIN/NODATA(QTYPE=ANY) negative
+			 * non-ancient NXDOMAIN/NODATA(QTYPE=ANY) negative
 			 * cache entry.  If we're adding an RRSIG, also
-			 * check for an extant non-stale NODATA ncache
+			 * check for an extant non-ancient NODATA ncache
 			 * entry which covers the same type as the RRSIG.
 			 */
 			for (topheader = rbtnode->data;
@@ -6533,7 +6584,7 @@ addrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
 	 * If we're adding a delegation type, adding to the auxiliary NSEC tree,
 	 * or the DB is a cache in an overmem state, hold an exclusive lock on
 	 * the tree.  In the latter case the lock does not necessarily have to
-	 * be acquired but it will help purge stale entries more effectively.
+	 * be acquired but it will help purge ancient entries more effectively.
 	 */
 	if (IS_CACHE(rbtdb) && isc_mem_isovermem(rbtdb->common.mctx))
 		cache_is_overmem = true;