diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -74,6 +74,8 @@
 #include <sys/epoch.h>
 #endif
 
+volatile uint32_t __read_frequently hpts_that_need_softclock = 0;
+
 void	(*tcp_hpts_softclock)(void);
 
 /*
diff --git a/sys/netinet/tcp_hpts.c b/sys/netinet/tcp_hpts.c
--- a/sys/netinet/tcp_hpts.c
+++ b/sys/netinet/tcp_hpts.c
@@ -193,7 +193,8 @@
 	uint8_t p_direct_wake :1, /* boolean */
 		p_on_min_sleep:1, /* boolean */
 		p_hpts_wake_scheduled:1, /* boolean */
-		p_avail:5;
+		hit_callout_thresh:1,
+		p_avail:4;
 	uint8_t p_fill[3];	  /* Fill to 32 bits */
 	/* Cache line 0x40 */
 	struct hptsh {
@@ -1683,6 +1684,13 @@
 	ticks_ran = tcp_hptsi(hpts, 1);
 	tv.tv_sec = 0;
 	tv.tv_usec = hpts->p_hpts_sleep_time * HPTS_TICKS_PER_SLOT;
+	if ((hpts->p_on_queue_cnt > conn_cnt_thresh) && (hpts->hit_callout_thresh == 0)) {
+		hpts->hit_callout_thresh = 1;
+		atomic_add_int(&hpts_that_need_softclock, 1);
+	} else if ((hpts->p_on_queue_cnt <= conn_cnt_thresh) && (hpts->hit_callout_thresh == 1)) {
+		hpts->hit_callout_thresh = 0;
+		atomic_subtract_int(&hpts_that_need_softclock, 1);
+	}
 	if (hpts->p_on_queue_cnt >= conn_cnt_thresh) {
 		if(hpts->p_direct_wake == 0) {
 			/*
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -400,8 +400,10 @@
 extern int	cpu_disable_c3_sleep;
 
 extern void	(*tcp_hpts_softclock)(void);
+extern volatile uint32_t __read_frequently hpts_that_need_softclock;
+
 #define	tcp_hpts_softclock()	do {					\
-		if (tcp_hpts_softclock != NULL)				\
+		if (hpts_that_need_softclock > 0)			\
 			tcp_hpts_softclock();				\
 } while (0)