diff --git a/man/syslogd.8 b/man/syslogd.8
index 9a93b8f..dcfb564 100644
--- a/man/syslogd.8
+++ b/man/syslogd.8
@@ -296,7 +296,9 @@ facility is reserved for messages read directly from
 Select the number of minutes between
 .Dq mark
 messages; the default is 20 minutes.  Setting this to zero disables log
-marks.
+marks.  See the
+.Sx BUGS
+section for more information.
 .It Fl n
 Disable DNS query for every request.
 .It Fl p Ar socket
@@ -622,6 +624,22 @@ from should be put early into the
 .Fl a
 list.
 .Pp
+The mark interval, as controlled by the
+.Fl m Ar INTV
+option, relies on an internal timer with 30 second granularity.  Every
+30 seconds
+.Nm
+will attempt to log the text
+.Cd "-- MARK --"
+with (the internal) facility
+.Cd mark
+and priority
+.Cd info .
+Every log target is traversed, if at least
+.Ar INTV
+minutes have passed since the log target was written to, the mark is
+logged.  Hence, it may be off by up to 30 seconds, this is by design.
+.Pp
 As mentioned in the
 .Sx DESCRIPTION ,
 .Nm
diff --git a/src/syslogd.c b/src/syslogd.c
index b63e030..0d8a3d7 100644
--- a/src/syslogd.c
+++ b/src/syslogd.c
@@ -585,13 +585,8 @@ no_klogd:
 	/*
 	 * Set up timer callbacks for -- MARK -- et al
 	 */
-	if (MarkInterval > 0) {
-		int interval = MarkInterval / 2;
-
-		if (interval < 30)
-			interval = 30;
-		timer_add(interval, domark, NULL);
-	}
+	if (MarkInterval > 0)
+		timer_add(TIMERINTVL, domark, NULL);
 	timer_add(TIMERINTVL, doflush, NULL);
 
 	/* Start 'em */
@@ -1674,11 +1669,7 @@ static void logmsg(struct buf_msg *buffer)
 
 		/* don't output marks to recently written files */
 		if (buffer->flags & MARK) {
-			time_t t_now = timer_now();
-
-			if (f->f_time + MarkInterval > t_now)
-				continue;
-			if (t_now - f->f_time < MarkInterval / 2)
+			if (timer_now() - f->f_time < MarkInterval)
 				continue;
 		}
 
@@ -2423,14 +2414,7 @@ static void forw_lookup(struct filed *f)
 
 void domark(void *arg)
 {
-	static time_t t_last = 0;
-	time_t t_now;
-
-	t_now = timer_now();
-	if (t_now >= t_last + MarkInterval) {
-		flog(INTERNAL_MARK | LOG_INFO, "-- MARK --");
-		t_last = t_now;
-	}
+	flog(INTERNAL_MARK | LOG_INFO, "-- MARK --");
 }
 
 void doflush(void *arg)