diff --git a/bind-9.16-nodelock-count.patch b/bind-9.16-nodelock-count.patch
deleted file mode 100644
index 4462811..0000000
--- a/bind-9.16-nodelock-count.patch
+++ /dev/null
@@ -1,38 +0,0 @@
-From 33e5888cb723bb43bc622eaa8ded2c9f383e4a54 Mon Sep 17 00:00:00 2001
-From: =?UTF-8?q?Petr=20Men=C5=A1=C3=ADk?= <pemensik@redhat.com>
-Date: Thu, 19 Aug 2021 16:58:14 +0200
-Subject: [PATCH] Revert "Reduce the nodelock count for both cache and regular
- rbtdb"
-
-This reverts commit bceda720e420cd22e60c7a407535746281efb33b.
-
-https://gitlab.isc.org/isc-projects/bind9/-/issues/2872
----
- lib/dns/rbtdb.c | 4 ++--
- 1 file changed, 2 insertions(+), 2 deletions(-)
-
-diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c
-index 18503950ad..5c37b7d049 100644
---- a/lib/dns/rbtdb.c
-+++ b/lib/dns/rbtdb.c
-@@ -348,7 +348,7 @@ typedef ISC_LIST(dns_rbtnode_t) rbtnodelist_t;
- 	(((header)->rdh_ttl > (now)) || \
- 	 ((header)->rdh_ttl == (now) && ZEROTTL(header)))
- 
--#define DEFAULT_NODE_LOCK_COUNT	    7 /*%< Should be prime. */
-+#define DEFAULT_NODE_LOCK_COUNT	    53 /*%< Should be prime. */
- #define RBTDB_GLUE_TABLE_INIT_BITS  2U
- #define RBTDB_GLUE_TABLE_MAX_BITS   32U
- #define RBTDB_GLUE_TABLE_OVERCOMMIT 3
-@@ -380,7 +380,7 @@ hash_32(uint32_t val, unsigned int bits) {
- #define DEFAULT_CACHE_NODE_LOCK_COUNT DNS_RBTDB_CACHE_NODE_LOCK_COUNT
- #endif /* if DNS_RBTDB_CACHE_NODE_LOCK_COUNT <= 1 */
- #else  /* ifdef DNS_RBTDB_CACHE_NODE_LOCK_COUNT */
--#define DEFAULT_CACHE_NODE_LOCK_COUNT 17
-+#define DEFAULT_CACHE_NODE_LOCK_COUNT 97
- #endif /* DNS_RBTDB_CACHE_NODE_LOCK_COUNT */
- 
- typedef struct {
--- 
-2.31.1
-
diff --git a/bind-9.16.20-map-format-fix.patch b/bind-9.16.20-map-format-fix.patch
new file mode 100644
index 0000000..f6e3c9b
--- /dev/null
+++ b/bind-9.16.20-map-format-fix.patch
@@ -0,0 +1,8 @@
+--- a/lib/dns/mapapi
++++ b/lib/dns/mapapi
+@@ -13,4 +13,4 @@
+ # Whenever releasing a new major release of BIND9, set this value
+ # back to 1.0 when releasing the first alpha.  Map files are *never*
+ # compatible across major releases.
+-MAPAPI=2.0
++MAPAPI=3.0
diff --git a/bind.spec b/bind.spec
index ef281b9..d020de0 100644
--- a/bind.spec
+++ b/bind.spec
@@ -53,7 +53,7 @@ Summary:  The Berkeley Internet Name Domain (BIND) DNS (Domain Name System) serv
 Name:     bind
 License:  MPLv2.0
 Version:  9.16.20
-Release:  2%{?dist}
+Release:  3%{?dist}
 Epoch:    32
 Url:      https://www.isc.org/downloads/bind/
 #
@@ -105,7 +105,7 @@ Patch164:bind-9.11-rh1666814.patch
 Patch170:bind-9.11-feature-test-named.patch
 Patch171:bind-9.11-tests-variants.patch
 # https://gitlab.isc.org/isc-projects/bind9/-/issues/2872
-Patch172:bind-9.16-nodelock-count.patch
+Patch172:https://downloads.isc.org/isc/bind9/9.16.20/patches/bind-9.16.20-map-format-fix.patch
 
 %{?systemd_ordering}
 Requires:       coreutils
@@ -406,7 +406,7 @@ in HTML and PDF format.
 %patch164 -p1 -b .rh1666814
 %patch170 -p1 -b .featuretest-named
 %patch171 -p1 -b .test-variant
-%patch172 -p1 -b .node-count
+%patch172 -p1 -b .map-format
 
 %if %{with PKCS11}
 %patch135 -p1 -b .config-pkcs11
@@ -1130,6 +1130,9 @@ fi;
 %endif
 
 %changelog
+* Wed Aug 25 2021 Petr Menšík <pemensik@redhat.com> - 32:9.16.20-3
+- Increase map format version, lower memory consuption a bit (#1997504)
+
 * Thu Aug 19 2021 Petr Menšík <pemensik@redhat.com> - 32:9.16.20-2
 - Fix map file format regression