Reference: https://src.fedoraproject.org/rpms/dhcp/blob/rawhide/f/0021-Load-leases-DB-in-non-replay-mode-only.patch
From bdbbb4be07bb33fe083baef2bd0ef38b91c11120 Mon Sep 17 00:00:00 2001
From: Pavel Zhukov <pzhukov@redhat.com>
Date: Thu, 21 Feb 2019 10:44:06 +0100
Subject: [PATCH 21/28] Load leases DB in non-replay mode only

---
 server/confpars.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/server/confpars.c b/server/confpars.c
index 5a6396b..6e08ad7 100644
--- a/server/confpars.c
+++ b/server/confpars.c
@@ -134,6 +134,11 @@ isc_result_t read_conf_file (const char *filename, struct group *group,
 
 	cfile = (struct parse *)0;
 #if defined (TRACING)
+	// No need to dmalloc huge memory region if we're not going to re-play
+	if (!trace_record()){
+		status = new_parse(&cfile, file, NULL, 0, filename, 0);
+		goto noreplay;
+	};
 	flen = lseek (file, (off_t)0, SEEK_END);
 	if (flen < 0) {
 	      boom:
@@ -165,7 +170,6 @@ isc_result_t read_conf_file (const char *filename, struct group *group,
 	if (result != ulen)
 		log_fatal ("%s: short read of %d bytes instead of %d.",
 			   filename, ulen, result);
-	close (file);
       memfile:
 	/* If we're recording, write out the filename and file contents. */
 	if (trace_record ())
@@ -174,6 +178,9 @@ isc_result_t read_conf_file (const char *filename, struct group *group,
 #else
 	status = new_parse(&cfile, file, NULL, 0, filename, 0);
 #endif
+      noreplay:
+	if (!trace_playback())
+		close (file);
 	if (status != ISC_R_SUCCESS || cfile == NULL)
 		return status;
 
@@ -183,7 +190,8 @@ isc_result_t read_conf_file (const char *filename, struct group *group,
 		status = conf_file_subparse (cfile, group, group_type);
 	end_parse (&cfile);
 #if defined (TRACING)
-	dfree (dbuf, MDL);
+	if (trace_record())
+	    dfree (dbuf, MDL);
 #endif
 	return status;
 }
-- 
2.35.1