diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
index a14a2eb..4710985 100644
--- a/lib/dpif-netdev.c
+++ b/lib/dpif-netdev.c
@@ -344,6 +344,8 @@ struct dp_netdev_rxq {
     struct dp_netdev_pmd_thread *pmd;  /* pmd thread that will poll this queue. */
 };
 
+#define LAST_USED_QID_NONE -1
+
 /* A port in a netdev-based datapath. */
 struct dp_netdev_port {
     odp_port_t port_no;
@@ -494,6 +496,8 @@ struct tx_port {
     int qid;
     long long last_used;
     struct hmap_node node;
+    int last_used_qid;    /* Last queue id where packets could be
+                             enqueued. */
 };
 
 /* PMD: Poll modes drivers.  PMD accesses devices via polling to eliminate
@@ -3033,6 +3037,26 @@ cycles_count_end(struct dp_netdev_pmd_thread *pmd,
 }
 
 static void
+dp_netdev_drain_txq_ports(struct dp_netdev_pmd_thread *pmd)
+{
+    struct tx_port *cached_tx_port;
+    int tx_qid;
+
+    HMAP_FOR_EACH (cached_tx_port, node, &pmd->send_port_cache) {
+        tx_qid = cached_tx_port->last_used_qid;
+
+        if (tx_qid != LAST_USED_QID_NONE) {
+            netdev_txq_drain(cached_tx_port->port->netdev, tx_qid,
+                         cached_tx_port->port->dynamic_txqs);
+
+            /* Queue drained and mark it empty. */
+            cached_tx_port->last_used_qid = LAST_USED_QID_NONE;
+        }
+    }
+}
+
+
+static void
 dp_netdev_process_rxq_port(struct dp_netdev_pmd_thread *pmd,
                            struct netdev_rxq *rx,
                            odp_port_t port_no)
@@ -3647,15 +3671,18 @@ pmd_load_queues_and_ports(struct dp_netdev_pmd_thread *pmd,
     return i;
 }
 
+enum { DRAIN_TSC = 20000ULL };
+
 static void *
 pmd_thread_main(void *f_)
 {
     struct dp_netdev_pmd_thread *pmd = f_;
-    unsigned int lc = 0;
+    unsigned int lc = 0, lc_drain = 0;
     struct polled_queue *poll_list;
     bool exiting;
     int poll_cnt;
     int i;
+    uint64_t prev = 0, now = 0;
 
     poll_list = NULL;
 
@@ -3688,6 +3715,17 @@ reload:
                                        poll_list[i].port_no);
         }
 
+#define MAX_LOOP_TO_DRAIN 128
+        if (lc_drain++ > MAX_LOOP_TO_DRAIN) {
+            lc_drain = 0;
+            prev = now;
+            now = pmd->last_cycles;
+
+            if ((now - prev) > DRAIN_TSC) {
+                dp_netdev_drain_txq_ports(pmd);
+            }
+        }
+
         if (lc++ > 1024) {
             bool reload;
 
@@ -4330,6 +4368,7 @@ dp_netdev_add_port_tx_to_pmd(struct dp_netdev_pmd_thread *pmd,
 
     tx->port = port;
     tx->qid = -1;
+    tx->last_used_qid = LAST_USED_QID_NONE;
 
     hmap_insert(&pmd->tx_ports, &tx->node, hash_port_no(tx->port->port_no));
     pmd->need_reload = true;
@@ -4892,6 +4931,14 @@ dpif_netdev_xps_get_tx_qid(const struct dp_netdev_pmd_thread *pmd,
 
     dpif_netdev_xps_revalidate_pmd(pmd, now, false);
 
+    /* The tx queue can change in XPS case, make sure packets in previous
+     * queue is drained properly. */
+    if (tx->last_used_qid != LAST_USED_QID_NONE &&
+               tx->qid != tx->last_used_qid) {
+        netdev_txq_drain(port->netdev, tx->last_used_qid, port->dynamic_txqs);
+        tx->last_used_qid = LAST_USED_QID_NONE;
+    }
+
     VLOG_DBG("Core %d: New TX queue ID %d for port \'%s\'.",
              pmd->core_id, tx->qid, netdev_get_name(tx->port->netdev));
     return min_qid;
@@ -4987,6 +5034,8 @@ dp_execute_cb(void *aux_, struct dp_packet_batch *packets_,
                 tx_qid = pmd->static_tx_qid;
             }
 
+            p->last_used_qid = tx_qid;
+
             netdev_send(p->port->netdev, tx_qid, packets_, may_steal,
                         dynamic_txqs);
             return;
diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
index ddc651b..26cfa85 100644
--- a/lib/netdev-dpdk.c
+++ b/lib/netdev-dpdk.c
@@ -286,6 +286,11 @@ struct dpdk_mp {
     struct ovs_list list_node OVS_GUARDED_BY(dpdk_mp_mutex);
 };
 
+/* Queue 'INTERIM_QUEUE_BURST_THRESHOLD' packets before tranmitting.
+ * Defaults to 'NETDEV_MAX_BURST'(32) now.
+ */
+#define INTERIM_QUEUE_BURST_THRESHOLD NETDEV_MAX_BURST
+
 /* There should be one 'struct dpdk_tx_queue' created for
  * each cpu core. */
 struct dpdk_tx_queue {
@@ -295,6 +300,11 @@ struct dpdk_tx_queue {
                                     * pmd threads (see 'concurrent_txq'). */
     int map;                       /* Mapping of configured vhost-user queues
                                     * to enabled by guest. */
+    struct dp_packet *pkts[INTERIM_QUEUE_BURST_THRESHOLD];
+                                   /* Intermediate queue where packets can
+                                    * be buffered for vhost ports */
+    int pkt_cnt;                   /* Number of packets waiting to be sent on
+                                    * vhost port */
 };
 
 /* dpdk has no way to remove dpdk ring ethernet devices
@@ -1666,6 +1676,61 @@ netdev_dpdk_vhost_update_tx_counters(struct netdev_stats *stats,
     }
 }
 
+static int
+netdev_dpdk_vhost_tx_burst(struct netdev_dpdk *dev, int qid,
+                           int dropped)
+{
+    struct dpdk_tx_queue *txq = &dev->tx_q[qid];
+    struct rte_mbuf **cur_pkts = (struct rte_mbuf **)txq->pkts;
+
+    int tx_vid = netdev_dpdk_get_vid(dev);
+    int tx_qid = qid * VIRTIO_QNUM + VIRTIO_RXQ;
+    uint32_t sent=0;
+    uint32_t retries=0;
+    uint32_t sum=0;
+    uint32_t total_pkts = 0;
+
+    total_pkts = sum = txq->pkt_cnt;
+    do {
+        uint32_t ret;
+        ret = rte_vhost_enqueue_burst(tx_vid, tx_qid, &cur_pkts[sent], sum);
+        if (!ret) {
+            /* No packets enqueued - do not retry. */
+            break;
+        } else {
+            /* Packet have been sent */
+            sent += ret;
+
+            /* 'sum; packet have to be retransmitted */
+            sum -= ret;
+        }
+    } while (sum && (retries++ < VHOST_ENQ_RETRY_NUM));
+
+    for (int i=0; i < total_pkts - dropped; i++) {
+        dp_packet_delete(txq->pkts[i]);
+    }
+
+    /* Reset pkt count */
+    txq->pkt_cnt = 0;
+
+    /* 'sum' refers to packets dropped */
+    return sum;
+}
+
+static int
+netdev_dpdk_vhost_txq_drain(struct netdev *netdev, int qid,
+                            bool concurrent_txq OVS_UNUSED)
+{
+    struct netdev_dpdk *dev = netdev_dpdk_cast(netdev);
+    struct dpdk_tx_queue *txq = &dev->tx_q[qid];
+
+    if (OVS_LIKELY(txq->pkt_cnt)) {
+        netdev_dpdk_vhost_tx_burst(dev, qid, 0);
+    }
+
+    return 0;
+}
+
 static void
 __netdev_dpdk_vhost_send(struct netdev *netdev, int qid,
                          struct dp_packet **pkts, int cnt)
@@ -1674,16 +1739,20 @@ __netdev_dpdk_vhost_send(struct netdev *netdev, int qid,
     struct rte_mbuf **cur_pkts = (struct rte_mbuf **) pkts;
     unsigned int total_pkts = cnt;
     unsigned int dropped = 0;
-    int i, retries = 0;
+    int i;
 
     qid = dev->tx_q[qid % netdev->n_txq].map;
+    struct dpdk_tx_queue *txq = &dev->tx_q[qid];
 
     if (OVS_UNLIKELY(!is_vhost_running(dev) || qid < 0
                      || !(dev->flags & NETDEV_UP))) {
         rte_spinlock_lock(&dev->stats_lock);
         dev->stats.tx_dropped+= cnt;
         rte_spinlock_unlock(&dev->stats_lock);
-        goto out;
+
+        for (i = 0; i < total_pkts; i++) {
+            dp_packet_delete(pkts[i]);
+        }
     }
 
     rte_spinlock_lock(&dev->tx_q[qid].tx_lock);
@@ -1693,34 +1762,21 @@ __netdev_dpdk_vhost_send(struct netdev *netdev, int qid,
     cnt = netdev_dpdk_qos_run(dev, cur_pkts, cnt);
     dropped = total_pkts - cnt;
 
-    do {
-        int vhost_qid = qid * VIRTIO_QNUM + VIRTIO_RXQ;
-        unsigned int tx_pkts;
-
-        tx_pkts = rte_vhost_enqueue_burst(netdev_dpdk_get_vid(dev),
-                                          vhost_qid, cur_pkts, cnt);
-        if (OVS_LIKELY(tx_pkts)) {
-            /* Packets have been sent.*/
-            cnt -= tx_pkts;
-            /* Prepare for possible retry.*/
-            cur_pkts = &cur_pkts[tx_pkts];
-        } else {
-            /* No packets sent - do not retry.*/
-            break;
+    int idx = 0;
+    while (idx < cnt) {
+        txq->pkts[txq->pkt_cnt++] = pkts[idx++];
+
+        if (txq->pkt_cnt >= INTERIM_QUEUE_BURST_THRESHOLD) {
+            dropped += netdev_dpdk_vhost_tx_burst(dev, qid, dropped);
         }
-    } while (cnt && (retries++ <= VHOST_ENQ_RETRY_NUM));
+    }
 
     rte_spinlock_unlock(&dev->tx_q[qid].tx_lock);
 
     rte_spinlock_lock(&dev->stats_lock);
     netdev_dpdk_vhost_update_tx_counters(&dev->stats, pkts, total_pkts,
-                                         cnt + dropped);
+                                         dropped);
     rte_spinlock_unlock(&dev->stats_lock);
-
-out:
-    for (i = 0; i < total_pkts - dropped; i++) {
-        dp_packet_delete(pkts[i]);
-    }
 }
 
 /* Tx function. Transmit packets indefinitely */
@@ -3247,7 +3303,7 @@ unlock:
                           SET_CONFIG, SET_TX_MULTIQ, SEND,    \
                           GET_CARRIER, GET_STATS,             \
                           GET_FEATURES, GET_STATUS,           \
-                          RECONFIGURE, RXQ_RECV)              \
+                          RECONFIGURE, RXQ_RECV, TXQ_DRAIN)   \
 {                                                             \
     NAME,                                                     \
     true,                       /* is_pmd */                  \
@@ -3314,6 +3370,7 @@ unlock:
     RXQ_RECV,                                                 \
     NULL,                       /* rx_wait */                 \
     NULL,                       /* rxq_drain */               \
+    TXQ_DRAIN,                  /* txq_drain */               \
 }
 
 static const struct netdev_class dpdk_class =
@@ -3330,7 +3387,8 @@ static const struct netdev_class dpdk_class =
         netdev_dpdk_get_features,
         netdev_dpdk_get_status,
         netdev_dpdk_reconfigure,
-        netdev_dpdk_rxq_recv);
+        netdev_dpdk_rxq_recv,
+        NULL);
 
 static const struct netdev_class dpdk_ring_class =
     NETDEV_DPDK_CLASS(
@@ -3346,7 +3404,8 @@ static const struct netdev_class dpdk_ring_class =
         netdev_dpdk_get_features,
         netdev_dpdk_get_status,
         netdev_dpdk_reconfigure,
-        netdev_dpdk_rxq_recv);
+        netdev_dpdk_rxq_recv,
+        NULL);
 
 static const struct netdev_class dpdk_vhost_class =
     NETDEV_DPDK_CLASS(
@@ -3362,7 +3421,8 @@ static const struct netdev_class dpdk_vhost_class =
         NULL,
         NULL,
         netdev_dpdk_vhost_reconfigure,
-        netdev_dpdk_vhost_rxq_recv);
+        netdev_dpdk_vhost_rxq_recv,
+        netdev_dpdk_vhost_txq_drain);
 static const struct netdev_class dpdk_vhost_client_class =
     NETDEV_DPDK_CLASS(
         "dpdkvhostuserclient",
@@ -3377,7 +3437,8 @@ static const struct netdev_class dpdk_vhost_client_class =
         NULL,
         NULL,
         netdev_dpdk_vhost_client_reconfigure,
-        netdev_dpdk_vhost_rxq_recv);
+        netdev_dpdk_vhost_rxq_recv,
+        netdev_dpdk_vhost_txq_drain);
 
 void
 netdev_dpdk_register(void)
diff --git a/lib/netdev-dummy.c b/lib/netdev-dummy.c
index 0657434..4ef659e 100644
--- a/lib/netdev-dummy.c
+++ b/lib/netdev-dummy.c
@@ -1409,6 +1409,7 @@ netdev_dummy_update_flags(struct netdev *netdev_,
     netdev_dummy_rxq_recv,                                      \
     netdev_dummy_rxq_wait,                                      \
     netdev_dummy_rxq_drain,                                     \
+    NULL,                                                       \
 }
 
 static const struct netdev_class dummy_class =
diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 9ff1333..79478ee 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -2830,6 +2830,7 @@ netdev_linux_update_flags(struct netdev *netdev_, enum netdev_flags off,
     netdev_linux_rxq_recv,                                      \
     netdev_linux_rxq_wait,                                      \
     netdev_linux_rxq_drain,                                     \
+    NULL,                                                       \
 }
 
 const struct netdev_class netdev_linux_class =
diff --git a/lib/netdev-provider.h b/lib/netdev-provider.h
index 8346fc4..5dd68db 100644
--- a/lib/netdev-provider.h
+++ b/lib/netdev-provider.h
@@ -769,6 +769,9 @@ struct netdev_class {
 
     /* Discards all packets waiting to be received from 'rx'. */
     int (*rxq_drain)(struct netdev_rxq *rx);
+
+    /* Drain all packets waiting to be sent on queue 'qid'. */
+    int (*txq_drain)(struct netdev *netdev, int qid, bool concurrent_txq);
 };
 
 int netdev_register_provider(const struct netdev_class *);
diff --git a/lib/netdev-vport.c b/lib/netdev-vport.c
index 39093e8..eb4b7d2 100644
--- a/lib/netdev-vport.c
+++ b/lib/netdev-vport.c
@@ -847,7 +847,8 @@ get_stats(const struct netdev *netdev, struct netdev_stats *stats)
     NULL,                   /* rx_dealloc */                \
     NULL,                   /* rx_recv */                   \
     NULL,                   /* rx_wait */                   \
-    NULL,                   /* rx_drain */
+    NULL,                   /* rx_drain */                  \
+    NULL,                   /* tx_drain */
 
 
 #define TUNNEL_CLASS(NAME, DPIF_PORT, BUILD_HEADER, PUSH_HEADER, POP_HEADER)   \
diff --git a/lib/netdev.c b/lib/netdev.c
index a8d8eda..b486b5d 100644
--- a/lib/netdev.c
+++ b/lib/netdev.c
@@ -678,6 +678,15 @@ netdev_rxq_drain(struct netdev_rxq *rx)
             : 0);
 }
 
+/* Flush packets on the queue 'qid'. */
+int
+netdev_txq_drain(struct netdev *netdev, int qid, bool netdev_txq_drain)
+{
+    return (netdev->netdev_class->txq_drain
+            ? netdev->netdev_class->txq_drain(netdev, qid, netdev_txq_drain)
+            : EOPNOTSUPP);
+}
+
 /* Configures the number of tx queues of 'netdev'. Returns 0 if successful,
  * otherwise a positive errno value.
  *
diff --git a/lib/netdev.h b/lib/netdev.h
index d6c07c1..7ddd790 100644
--- a/lib/netdev.h
+++ b/lib/netdev.h
@@ -155,6 +155,7 @@ int netdev_rxq_drain(struct netdev_rxq *);
 int netdev_send(struct netdev *, int qid, struct dp_packet_batch *,
                 bool may_steal, bool concurrent_txq);
 void netdev_send_wait(struct netdev *, int qid);
+int netdev_txq_drain(struct netdev *, int qid, bool concurrent_txq);
 
 /* native tunnel APIs */
 /* Structure to pass parameters required to build a tunnel header. */
