diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 335efc1c6f06..f81f2f38659e 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -43,6 +43,7 @@ unsigned int sysctl_sched_latency			= 6000000ULL;
 static unsigned int normalized_sysctl_sched_latency	= 6000000ULL;
 
 #ifdef CONFIG_CACULE_SCHED
+int cacule_max_lifetime					= 30000; // in ms
 int interactivity_factor				= 32768;
 #endif
 
@@ -591,22 +592,25 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
 static inline unsigned int
 calc_interactivity(u64 now, struct cacule_node *se)
 {
-	u64 l_se, vr_se, sleep_se, u64_factor;
+	u64 l_se, vr_se, sleep_se = 1ULL, u64_factor;
 	unsigned int score_se;
 
 	/*
 	 * in case of vruntime==0, logical OR with 1 would
 	 * make sure that the least sig. bit is 1
 	 */
-	l_se		= (now + 1ULL) - se->cacule_start_time;
+	l_se		= now - se->cacule_start_time;
 	vr_se		= se->vruntime		| 1;
-	sleep_se	= (l_se - vr_se)	| 1;
 	u64_factor	= interactivity_factor;
 
-	if (sleep_se > vr_se)
+	/* safety check */
+	if (likely(l_se > vr_se))
+		sleep_se = (l_se - vr_se) | 1;
+
+	if (sleep_se >= vr_se)
 		score_se = u64_factor / (sleep_se / vr_se);
 	else
-		score_se = (u64_factor / (vr_se / sleep_se)) + u64_factor;
+		score_se = (u64_factor << 1) - (u64_factor / (vr_se / sleep_se));
 
 	return score_se;
 }
@@ -964,6 +968,42 @@ static void update_tg_load_avg(struct cfs_rq *cfs_rq, int force)
 }
 #endif /* CONFIG_SMP */
 
+#ifdef CONFIG_CACULE_SCHED
+static void reset_lifetime(u64 now, struct sched_entity *se)
+{
+	struct cacule_node *cn;
+	u64 max_life_ns, life_time;
+	s64 diff;
+
+	/*
+	 * left shift 20 bits is approximately = * 1000000
+	 * we don't need the precision of life time
+	 * Ex. for 30s, with left shift (20bits) == 31.457s
+	 */
+	max_life_ns	= ((u64) cacule_max_lifetime) << 20;
+
+	for_each_sched_entity(se) {
+		cn		= &se->cacule_node;
+		life_time	= now - cn->cacule_start_time;
+		diff		= life_time - max_life_ns;
+
+		if (unlikely(diff > 0)) {
+			// multiply life_time by 8 for more precision
+			u64 old_hrrn_x8	= life_time / ((cn->vruntime >> 3) | 1);
+
+			// reset life to half max_life (i.e ~15s)
+			cn->cacule_start_time = now - (max_life_ns >> 1);
+
+			// avoid division by zero
+			if (old_hrrn_x8 == 0) old_hrrn_x8 = 1;
+
+			// reset vruntime based on old hrrn ratio
+			cn->vruntime = (max_life_ns << 2) / old_hrrn_x8;
+		}
+	}
+}
+#endif /* CONFIG_CACULE_SCHED */
+
 /*
  * Update the current task's runtime statistics.
  */
@@ -991,6 +1031,7 @@ static void update_curr(struct cfs_rq *cfs_rq)
 
 #ifdef CONFIG_CACULE_SCHED
 	curr->cacule_node.vruntime += calc_delta_fair(delta_exec, curr);
+	reset_lifetime(sched_clock(), curr);
 #else
 	curr->vruntime += calc_delta_fair(delta_exec, curr);
 	update_min_vruntime(cfs_rq);