diff --git a/kernel/sy_old/mars_main.c b/kernel/sy_old/mars_main.c
index 06c07f5a..eeb4ef6f 100644
--- a/kernel/sy_old/mars_main.c
+++ b/kernel/sy_old/mars_main.c
@@ -896,6 +896,7 @@ struct mars_rotate {
 	bool allow_update;
 	bool rot_activated;
 	bool old_fetch_on;
+	bool want_sync;
 	bool forbid_replay;
 	bool replay_mode;
 	bool todo_primary;
@@ -1351,7 +1352,11 @@ int parse_logfile_name(const char *str, int *seq, const char **host)
 }
 
 static
-int compare_replaylinks(struct mars_rotate *rot, const char *hosta, const char *hostb)
+int compare_replaylinks(struct mars_rotate *rot,
+			const char *hosta,
+			const char *hostb,
+			loff_t *save_a,
+			loff_t *save_b)
 {
 	const char *linka = path_make("%s/replay-%s", rot->parent_path, hosta);
 	const char *linkb = path_make("%s/replay-%s", rot->parent_path, hostb);
@@ -1399,6 +1404,10 @@ int compare_replaylinks(struct mars_rotate *rot, const char *hosta, const char *
 		goto done;
 	}
 
+	/* The seqence number is equal.
+	 * Now the base offsets are comparable.
+	 */
+
 	posa += skip_part(a + posa);
 	posb += skip_part(b + posb);
 	if (unlikely(!a[posa++])) {
@@ -1411,11 +1420,13 @@ int compare_replaylinks(struct mars_rotate *rot, const char *hosta, const char *
 	count = sscanf(a + posa, "%lld", &offa);
 	if (unlikely(count != 1)) {
 		MARS_ERR_TO(rot->log_say, "replay link '%s' -> '%s' is malformed\n", linka, a);
-	}
+	} else if (save_a)
+		*save_a = offa;
 	count = sscanf(b + posb, "%lld", &offb);
 	if (unlikely(count != 1)) {
 		MARS_ERR_TO(rot->log_say, "replay link '%s' -> '%s' is malformed\n", linkb, b);
-	}
+	} else if (save_b)
+		*save_b = offb;
 
 	if (offa < offb) {
 		res = -1;
@@ -4700,6 +4711,35 @@ int _check_logging_status(struct mars_rotate *rot, int *log_nr, long long *oldpo
  check_pos:
 	*newpos = rot->aio_info.current_size;
 
+	/* Shorten the end position when sync wants to run.
+	 * Avoids unnecessary delay when the sync is starting again.
+	 */
+	if (rot->want_sync && !rot->todo_primary && rot->parent_path) {
+		loff_t min_pos = -1;
+		char  *tmp = path_make("%s/primary", rot->parent_path);
+		const char *primary = ordered_readlink(tmp, NULL);
+
+		if (likely(primary && primary[0])) {
+			int cmp = compare_replaylinks(rot, primary, my_id(), &min_pos, NULL);
+
+			MARS_DBG("want_sync compare=%d min_pos=%lld\n",
+				 cmp, min_pos);
+		}
+		if (min_pos >= 0 &&
+		    min_pos < *newpos) {
+			MARS_INF("shortening replay from %lld to %lld due to sync\n",
+				 *newpos, min_pos);
+			*newpos = min_pos;
+		}
+		if (unlikely(*oldpos_end > *newpos)) {
+			MARS_INF("also shortening from %lld to %lld\n",
+				 *oldpos_end, *newpos);
+			*oldpos_end = min_pos;
+		}
+		brick_string_free(tmp);
+		brick_string_free(primary);
+	}
+
 	if (unlikely(rot->aio_info.current_size < *oldpos_start)) {
 		status = -EBADF;
 		/* Allow primary --force even when logfiles are truncated / damaged.
@@ -6291,6 +6331,7 @@ static int make_sync(struct mars_dent *dent)
 		if (_global_sync_nr > global_sync_limit && global_sync_limit > 0)
 			do_start = false;
 	}
+	rot->want_sync = do_start;
 
 	/* Disallow contemporary sync & logfile_replay
 	 */
@@ -6307,7 +6348,8 @@ static int make_sync(struct mars_dent *dent)
 		MARS_DBG("update info links\n");
 		write_info_links(rot);
 	}
-	rot->forbid_replay = (do_start && compare_replaylinks(rot, peer, my_id()) < 0);
+	rot->forbid_replay = (do_start &&
+			      compare_replaylinks(rot, peer, my_id(), NULL, NULL) < 0);
 	if (rot->forbid_replay) {
 		MARS_INF("cannot start sync because my data is newer than the remote one at '%s'!\n", peer);
 		do_start = false;