diff --git a/sys/kern/kern_clocksource.c b/sys/kern/kern_clocksource.c
--- a/sys/kern/kern_clocksource.c
+++ b/sys/kern/kern_clocksource.c
@@ -175,6 +175,9 @@
 
 	state = DPCPU_PTR(timerstate);
 
+	/* make sure the time is properly aligned */
+	state->nexthard -= state->nexthard % tick_sbt;
+
 	runs = 0;
 	while (now >= state->nexthard) {
 		state->nexthard += tick_sbt;
@@ -317,7 +320,7 @@
 		next = &nexttick;
 	now = sbinuptime();
 	if (periodic)
-		*next = now + timerperiod;
+		*next = now - (now % timerperiod) + timerperiod;
 	else
 		*next = -1;	/* Next tick is not scheduled yet. */
 	state->now = now;
diff --git a/sys/kern/kern_timeout.c b/sys/kern/kern_timeout.c
--- a/sys/kern/kern_timeout.c
+++ b/sys/kern/kern_timeout.c
@@ -906,6 +906,8 @@
 			to_sbt = sbinuptime();
 		if ((flags & C_HARDCLOCK) == 0)
 			to_sbt += tick_sbt;
+		/* make sure the target time is really aligned to "tick_sbt" */
+		to_sbt -= to_sbt % tick_sbt;
 	} else
 		to_sbt = sbinuptime();
 	if (SBT_MAX - to_sbt < sbt)