diff --git a/cddl/contrib/opensolaris/cmd/zdb/zdb.c b/cddl/contrib/opensolaris/cmd/zdb/zdb.c
index 743641b560ba..ac9b06debf76 100644
--- a/cddl/contrib/opensolaris/cmd/zdb/zdb.c
+++ b/cddl/contrib/opensolaris/cmd/zdb/zdb.c
@@ -75,10 +75,12 @@
 	DMU_OT_ZAP_OTHER : DMU_OT_NUMTYPES))
 
 #ifndef lint
+extern int reference_tracking_enable;
 extern boolean_t zfs_recover;
 extern uint64_t zfs_arc_max, zfs_arc_meta_limit;
 extern int zfs_vdev_async_read_max_active;
 #else
+int reference_tracking_enable;
 boolean_t zfs_recover;
 uint64_t zfs_arc_max, zfs_arc_meta_limit;
 int zfs_vdev_async_read_max_active;
@@ -3696,6 +3698,11 @@ main(int argc, char **argv)
 	 */
 	zfs_vdev_async_read_max_active = 10;
 
+	/*
+	 * Disable reference tracking for better performance.
+	 */
+	reference_tracking_enable = B_FALSE;
+
 	kernel_init(FREAD);
 	g_zfs = libzfs_init();
 	if (g_zfs == NULL)