diff --git a/src/listener.c b/src/listener.c
index 3e080b4..a7e7290 100644
--- a/src/listener.c
+++ b/src/listener.c
@@ -597,6 +597,7 @@
 {
 	struct listener *l = fdtab[fd].owner;
 	struct proxy *p;
+	__decl_hathreads(unsigned long mask);
 	int max_accept;
 	int next_conn = 0;
 	int next_feconn = 0;
@@ -844,60 +845,116 @@
 		next_actconn = 0;
 
 #if defined(USE_THREAD)
-		count = l->bind_conf->thr_count;
-		if (count > 1 && (global.tune.options & GTUNE_LISTENER_MQ)) {
+		mask = thread_mask(l->bind_conf->bind_thread);
+		if (atleast2(mask) && (global.tune.options & GTUNE_LISTENER_MQ)) {
 			struct accept_queue_ring *ring;
-			int t1, t2, q1, q2;
+			unsigned int t, t0, t1, t2;
 
-			/* pick a first thread ID using a round robin index,
-			 * and a second thread ID using a random. The
-			 * connection will be assigned to the one with the
-			 * least connections. This provides fairness on short
+			/* The principle is that we have two running indexes,
+			 * each visiting in turn all threads bound to this
+			 * listener. The connection will be assigned to the one
+			 * with the least connections, and the other one will
+			 * be updated. This provides a good fairness on short
 			 * connections (round robin) and on long ones (conn
-			 * count).
+			 * count), without ever missing any idle thread.
 			 */
-			t1 = l->bind_conf->thr_idx;
+
+			/* keep a copy for the final update. thr_idx is composite
+			 * and made of (t2<<16) + t1.
+			 */
+			t0 = l->bind_conf->thr_idx;
 			do {
-				t2 = t1 + 1;
-				if (t2 >= count)
-					t2 = 0;
-			} while (!HA_ATOMIC_CAS(&l->bind_conf->thr_idx, &t1, t2));
+				unsigned long m1, m2;
+				int q1, q2;
+
+				t2 = t1 = t0;
+				t2 >>= 16;
+				t1 &= 0xFFFF;
+
+				/* t1 walks low to high bits ;
+				 * t2 walks high to low.
+				 */
+				m1 = mask >> t1;
+				m2 = mask & (t2 ? nbits(t2 + 1) : ~0UL);
+
+				if (unlikely((signed long)m2 >= 0)) {
+					/* highest bit not set */
+					if (!m2)
+						m2 = mask;
+
+					t2 = my_flsl(m2) - 1;
+				}
+
+				if (unlikely(!(m1 & 1) || t1 == t2)) {
+					m1 &= ~1UL;
+					if (!m1) {
+						m1 = mask;
+						t1 = 0;
+					}
+					t1 += my_ffsl(m1) - 1;
+				}
 
-			t2 = (random() >> 8) % (count - 1);  // 0..thr_count-2
-			t2 += t1 + 1;   // necessarily different from t1
+				/* now we have two distinct thread IDs belonging to the mask */
+				q1 = accept_queue_rings[t1].tail - accept_queue_rings[t1].head + ACCEPT_QUEUE_SIZE;
+				if (q1 >= ACCEPT_QUEUE_SIZE)
+					q1 -= ACCEPT_QUEUE_SIZE;
 
-			if (t2 >= count)
-				t2 -= count;
+				q2 = accept_queue_rings[t2].tail - accept_queue_rings[t2].head + ACCEPT_QUEUE_SIZE;
+				if (q2 >= ACCEPT_QUEUE_SIZE)
+					q2 -= ACCEPT_QUEUE_SIZE;
 
-			t1 = bind_map_thread_id(l->bind_conf, t1);
-			t2 = bind_map_thread_id(l->bind_conf, t2);
+				/* we have 3 possibilities now :
+				 *   q1 < q2 : t1 is less loaded than t2, so we pick it
+				 *             and update t2 (since t1 might still be
+				 *             lower than another thread)
+				 *   q1 > q2 : t2 is less loaded than t1, so we pick it
+				 *             and update t1 (since t2 might still be
+				 *             lower than another thread)
+				 *   q1 = q2 : both are equally loaded, thus we pick t1
+				 *             and update t1 as it will become more loaded
+				 *             than t2.
+				 */
 
-			q1 = accept_queue_rings[t1].tail - accept_queue_rings[t1].head + ACCEPT_QUEUE_SIZE;
-			if (q1 >= ACCEPT_QUEUE_SIZE)
-				q1 -= ACCEPT_QUEUE_SIZE;
+				q1 += l->thr_conn[t1];
+				q2 += l->thr_conn[t2];
 
-			q2 = accept_queue_rings[t2].tail - accept_queue_rings[t2].head + ACCEPT_QUEUE_SIZE;
-			if (q2 >= ACCEPT_QUEUE_SIZE)
-				q2 -= ACCEPT_QUEUE_SIZE;
+				if (q1 - q2 < 0) {
+					t = t1;
+					t2 = t2 ? t2 - 1 : LONGBITS - 1;
+				}
+				else if (q1 - q2 > 0) {
+					t = t2;
+					t1++;
+					if (t1 >= LONGBITS)
+						t1 = 0;
+				}
+				else {
+					t = t1;
+					t1++;
+					if (t1 >= LONGBITS)
+						t1 = 0;
+				}
 
-			/* make t1 the lowest loaded thread */
-			if (q1 >= ACCEPT_QUEUE_SIZE || l->thr_conn[t1] + q1 > l->thr_conn[t2] + q2)
-				t1 = t2;
+				/* new value for thr_idx */
+				t1 += (t2 << 16);
+			} while (unlikely(!HA_ATOMIC_CAS(&l->bind_conf->thr_idx, &t0, t1)));
 
-			/* We use deferred accepts even if it's the local thread because
-			 * tests show that it's the best performing model, likely due to
-			 * better cache locality when processing this loop.
+			/* We successfully selected the best thread "t" for this
+			 * connection. We use deferred accepts even if it's the
+			 * local thread because tests show that it's the best
+			 * performing model, likely due to better cache locality
+			 * when processing this loop.
 			 */
-			ring = &accept_queue_rings[t1];
+			ring = &accept_queue_rings[t];
 			if (accept_queue_push_mp(ring, cfd, l, &addr, laddr)) {
-				HA_ATOMIC_ADD(&activity[t1].accq_pushed, 1);
+				HA_ATOMIC_ADD(&activity[t].accq_pushed, 1);
 				task_wakeup(ring->task, TASK_WOKEN_IO);
 				continue;
 			}
 			/* If the ring is full we do a synchronous accept on
 			 * the local thread here.
 			 */
-			HA_ATOMIC_ADD(&activity[t1].accq_full, 1);
+			HA_ATOMIC_ADD(&activity[t].accq_full, 1);
 		}
 #endif // USE_THREAD