quic: Improve quic echo connect threading

Type: fix

Change-Id: I64f90139ad70e722f1ecbc4e0c6c1e723ec0f054
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>

3 files changed, 862 insertions, 725 deletions

diff --git a/src/plugins/hs_apps/sapi/echo_common.c b/src/plugins/hs_apps/sapi/echo_common.c
new file mode 100644
index 00000000000..a5c28145ba8
--- /dev/null
+++ b/src/plugins/hs_apps/sapi/echo_common.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2019 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <signal.h>
+
+#include <vnet/session/application_interface.h>
+
+typedef struct
+{
+  /* VNET_API_ERROR_FOO -> "Foo" hash table */
+  uword *error_string_by_error_number;
+} echo_common_main_t;
+
+echo_common_main_t echo_common_main;
+
+u8 *
+format_ip4_address (u8 * s, va_list * args)
+{
+  u8 *a = va_arg (*args, u8 *);
+  return format (s, "%d.%d.%d.%d", a[0], a[1], a[2], a[3]);
+}
+
+u8 *
+format_ip6_address (u8 * s, va_list * args)
+{
+  ip6_address_t *a = va_arg (*args, ip6_address_t *);
+  u32 i, i_max_n_zero, max_n_zeros, i_first_zero, n_zeros, last_double_colon;
+
+  i_max_n_zero = ARRAY_LEN (a->as_u16);
+  max_n_zeros = 0;
+  i_first_zero = i_max_n_zero;
+  n_zeros = 0;
+  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
+    {
+      u32 is_zero = a->as_u16[i] == 0;
+      if (is_zero && i_first_zero >= ARRAY_LEN (a->as_u16))
+	{
+	  i_first_zero = i;
+	  n_zeros = 0;
+	}
+      n_zeros += is_zero;
+      if ((!is_zero && n_zeros > max_n_zeros)
+	  || (i + 1 >= ARRAY_LEN (a->as_u16) && n_zeros > max_n_zeros))
+	{
+	  i_max_n_zero = i_first_zero;
+	  max_n_zeros = n_zeros;
+	  i_first_zero = ARRAY_LEN (a->as_u16);
+	  n_zeros = 0;
+	}
+    }
+
+  last_double_colon = 0;
+  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
+    {
+      if (i == i_max_n_zero && max_n_zeros > 1)
+	{
+	  s = format (s, "::");
+	  i += max_n_zeros - 1;
+	  last_double_colon = 1;
+	}
+      else
+	{
+	  s = format (s, "%s%x",
+		      (last_double_colon || i == 0) ? "" : ":",
+		      clib_net_to_host_u16 (a->as_u16[i]));
+	  last_double_colon = 0;
+	}
+    }
+
+  return s;
+}
+
+/* Format an IP46 address. */
+u8 *
+format_ip46_address (u8 * s, va_list * args)
+{
+  ip46_address_t *ip46 = va_arg (*args, ip46_address_t *);
+  ip46_type_t type = va_arg (*args, ip46_type_t);
+  int is_ip4 = 1;
+
+  switch (type)
+    {
+    case IP46_TYPE_ANY:
+      is_ip4 = ip46_address_is_ip4 (ip46);
+      break;
+    case IP46_TYPE_IP4:
+      is_ip4 = 1;
+      break;
+    case IP46_TYPE_IP6:
+      is_ip4 = 0;
+      break;
+    }
+
+  return is_ip4 ?
+    format (s, "%U", format_ip4_address, &ip46->ip4) :
+    format (s, "%U", format_ip6_address, &ip46->ip6);
+}
+
+static uword
+unformat_data (unformat_input_t * input, va_list * args)
+{
+  u64 _a;
+  u64 *a = va_arg (*args, u64 *);
+  if (unformat (input, "%lluGb", &_a))
+    *a = _a << 30;
+  else if (unformat (input, "%lluMb", &_a))
+    *a = _a << 20;
+  else if (unformat (input, "%lluKb", &_a))
+    *a = _a << 10;
+  else if (unformat (input, "%llu", a))
+    ;
+  else
+    return 0;
+  return 1;
+}
+
+static u8 *
+format_api_error (u8 * s, va_list * args)
+{
+  echo_common_main_t *ecm = &echo_common_main;
+  i32 error = va_arg (*args, u32);
+  uword *p;
+
+  p = hash_get (ecm->error_string_by_error_number, -error);
+
+  if (p)
+    s = format (s, "%s", p[0]);
+  else
+    s = format (s, "%d", error);
+  return s;
+}
+
+static void
+init_error_string_table ()
+{
+  echo_common_main_t *ecm = &echo_common_main;
+  ecm->error_string_by_error_number = hash_create (0, sizeof (uword));
+
+#define _(n,v,s) hash_set (ecm->error_string_by_error_number, -v, s);
+  foreach_vnet_api_error;
+#undef _
+
+  hash_set (ecm->error_string_by_error_number, 99, "Misc");
+}
+
diff --git a/src/plugins/hs_apps/sapi/quic_echo.c b/src/plugins/hs_apps/sapi/quic_echo.c
index 17a9e113a00..312b703d7e1 100644
--- a/src/plugins/hs_apps/sapi/quic_echo.c
+++ b/src/plugins/hs_apps/sapi/quic_echo.c
@@ -16,248 +16,15 @@
 #include <stdio.h>
 #include <signal.h>
 
-#include <vnet/session/application_interface.h>
 #include <vlibmemory/api.h>
 
 #include <vpp/api/vpe_msg_enum.h>
 #include <svm/fifo_segment.h>
-
-#define vl_typedefs		/* define message structures */
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_typedefs
-
-/* declare message handlers for each api */
-
-#define vl_endianfun		/* define message structures */
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_endianfun
-
-/* instantiate all the print functions we know about */
-#define vl_print(handle, ...)
-#define vl_printfun
-#include <vpp/api/vpe_all_api_h.h>
-#undef vl_printfun
-
-#define CHECK(expected, result, _fmt, _args...)		\
-    if (expected != result)				\
-      ECHO_FAIL ("expected %d, got %d : " _fmt, expected, result, ##_args);
-
-#define ECHO_FAIL(_fmt,_args...)	\
-  {					\
-    echo_main_t *em = &echo_main;	\
-    em->has_failed = 1;		\
-    em->time_to_stop = 1;		\
-    if (em->log_lvl > 1)		\
-      clib_warning ("ECHO-ERROR: "_fmt, ##_args); 	\
-  }
-
-#define ECHO_LOG(lvl, _fmt,_args...)	\
-  {					\
-    echo_main_t *em = &echo_main;	\
-    if (em->log_lvl > lvl)		\
-      clib_warning (_fmt, ##_args); 	\
-  }
-
-typedef struct
-{
-  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
-#define _(type, name) type name;
-  foreach_app_session_field
-#undef _
-  u64 vpp_session_handle;
-  u64 bytes_sent;
-  u64 bytes_to_send;
-  volatile u64 bytes_received;
-  volatile u64 bytes_to_receive;
-  f64 start;
-  u32 listener_index;		/* listener index in echo session pool */
-  u32 idle_cycles;		/* consecutive enq/deq with no data */
-  volatile u64 accepted_session_count;	/* sessions we accepted */
-} echo_session_t;
-
-typedef enum
-{
-  ECHO_NO_DATA_SOURCE,
-  ECHO_TEST_DATA_SOURCE,
-  ECHO_RX_DATA_SOURCE,
-  ECHO_INVALID_DATA_SOURCE
-} data_source_t;
-
-enum echo_close_f_t
-{
-  ECHO_CLOSE_F_INVALID = 0,
-  ECHO_CLOSE_F_PASSIVE,		/* wait for close msg */
-  ECHO_CLOSE_F_ACTIVE,		/* send close msg */
-  ECHO_CLOSE_F_NONE,		/* don't bother sending close msg */
-};
-
-enum quic_session_type_t
-{
-  QUIC_SESSION_TYPE_QUIC,
-  QUIC_SESSION_TYPE_STREAM,
-  QUIC_SESSION_TYPE_LISTEN,
-};
-
-enum quic_session_state_t
-{
-  QUIC_SESSION_STATE_INITIAL,
-  QUIC_SESSION_STATE_AWAIT_CLOSING,	/* Data transfer is done, wait for close evt */
-  QUIC_SESSION_STATE_AWAIT_DATA,	/* Peer closed, wait for outstanding data */
-  QUIC_SESSION_STATE_CLOSING,	/* told vpp to close */
-  QUIC_SESSION_STATE_CLOSED,	/* closed in vpp */
-};
-
-typedef enum
-{
-  STATE_START,
-  STATE_ATTACHED,
-  STATE_LISTEN,
-  STATE_READY,
-  STATE_DISCONNECTED,
-  STATE_DETACHED
-} connection_state_t;
-
-typedef enum echo_test_evt_
-{
-  ECHO_EVT_START = 1,		/* app starts */
-  ECHO_EVT_FIRST_QCONNECT = (1 << 1),	/* First connect Quic session sent */
-  ECHO_EVT_LAST_QCONNECTED = (1 << 2),	/* All Quic session are connected */
-  ECHO_EVT_FIRST_SCONNECT = (1 << 3),	/* First connect Stream session sent */
-  ECHO_EVT_LAST_SCONNECTED = (1 << 4),	/* All Stream session are connected */
-  ECHO_EVT_LAST_BYTE = (1 << 5),	/* Last byte received */
-  ECHO_EVT_EXIT = (1 << 6),	/* app exits */
-} echo_test_evt_t;
-
-typedef struct _quic_echo_cb_vft
-{
-  void (*quic_connected_cb) (session_connected_msg_t * mp, u32 session_index);
-  void (*client_stream_connected_cb) (session_connected_msg_t * mp,
-				      u32 session_index);
-  void (*server_stream_connected_cb) (session_connected_msg_t * mp,
-				      u32 session_index);
-  void (*quic_accepted_cb) (session_accepted_msg_t * mp, u32 session_index);
-  void (*client_stream_accepted_cb) (session_accepted_msg_t * mp,
-				     u32 session_index);
-  void (*server_stream_accepted_cb) (session_accepted_msg_t * mp,
-				     u32 session_index);
-} quic_echo_cb_vft_t;
-
-
-typedef enum
-{
-  RETURN_PACKETS_NOTEST,
-  RETURN_PACKETS_LOG_WRONG,
-  RETURN_PACKETS_ASSERT,
-} test_return_packets_t;
-
-typedef struct
-{
-  /* vpe input queue */
-  svm_queue_t *vl_input_queue;
-
-  /* API client handle */
-  u32 my_client_index;
-
-  /* The URI we're playing with */
-  u8 *uri;
-
-  /* Session pool */
-  echo_session_t *sessions;
-
-  /* Hash table for disconnect processing */
-  uword *session_index_by_vpp_handles;
-  /* Index of vpp listener session */
-  u32 listen_session_index;
-
-  /* Hash table for shared segment_names */
-  uword *shared_segment_handles;
-  clib_spinlock_t segment_handles_lock;
-
-  int i_am_master;
-
-  /* Our event queue */
-  svm_msg_q_t *our_event_queue;
-
-  u8 *socket_name;
-
-  pid_t my_pid;
-
-  /* For deadman timers */
-  clib_time_t clib_time;
-
-  /* State of the connection, shared between msg RX thread and main thread */
-  volatile connection_state_t state;
-
-  /* Signal variables */
-  volatile u8 time_to_stop;
-  u8 has_failed;
-
-  /* VNET_API_ERROR_FOO -> "Foo" hash table */
-  uword *error_string_by_error_number;
-
-  u8 *connect_test_data;
-  u8 test_return_packets;
-  u64 bytes_to_send;
-  u64 bytes_to_receive;
-  u32 fifo_size;
-  u32 rx_buf_size;
-  u32 tx_buf_size;
-  data_source_t data_source;
-  u8 send_quic_disconnects;	/* actively send disconnect */
-  u8 send_stream_disconnects;	/* actively send disconnect */
-  u8 output_json;
-  u8 log_lvl;
-
-  u8 *appns_id;
-  u64 appns_flags;
-  u64 appns_secret;
-
-  pthread_t *client_thread_handles;
-  u32 *thread_args;
-  u32 n_clients;		/* Target number of QUIC sessions */
-  u32 n_stream_clients;		/* Target Number of STREAM sessions per QUIC session */
-  volatile u32 n_quic_clients_connected;	/* Number of connected QUIC sessions */
-  volatile u32 n_clients_connected;	/* Number of STREAM sessions connected */
-  u32 n_rx_threads;		/* Number of data threads */
-
-  u64 tx_total;
-  u64 rx_total;
-
-  /* Event based timing : start & end depend on CLI specified events */
-  u8 events_sent;
-  f64 start_time;
-  f64 end_time;
-  u8 timing_start_event;
-  u8 timing_end_event;
-
-  /* cb vft for QUIC scenarios */
-  quic_echo_cb_vft_t cb_vft;
-
-  /** Flag that decides if socket, instead of svm, api is used to connect to
-   * vpp. If sock api is used, shm binary api is subsequently bootstrapped
-   * and all other messages are exchanged using shm IPC. */
-  u8 use_sock_api;
-
-  /* Limit the number of incorrect data messages */
-  int max_test_msg;
-
-  fifo_segment_main_t segment_main;
-} echo_main_t;
+#include <hs_apps/sapi/quic_echo.h>
+#include <hs_apps/sapi/echo_common.c>
 
 echo_main_t echo_main;
 
-#if CLIB_DEBUG > 0
-#define NITER 10000
-#else
-#define NITER 4000000
-#endif
-
-#if CLIB_DEBUG > 0
-#define TIMEOUT 10.0
-#else
-#define TIMEOUT 10.0
-#endif
-
 /*
  *
  *  Format functions
@@ -265,89 +32,6 @@ echo_main_t echo_main;
  */
 
 u8 *
-format_ip4_address (u8 * s, va_list * args)
-{
-  u8 *a = va_arg (*args, u8 *);
-  return format (s, "%d.%d.%d.%d", a[0], a[1], a[2], a[3]);
-}
-
-u8 *
-format_ip6_address (u8 * s, va_list * args)
-{
-  ip6_address_t *a = va_arg (*args, ip6_address_t *);
-  u32 i, i_max_n_zero, max_n_zeros, i_first_zero, n_zeros, last_double_colon;
-
-  i_max_n_zero = ARRAY_LEN (a->as_u16);
-  max_n_zeros = 0;
-  i_first_zero = i_max_n_zero;
-  n_zeros = 0;
-  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
-    {
-      u32 is_zero = a->as_u16[i] == 0;
-      if (is_zero && i_first_zero >= ARRAY_LEN (a->as_u16))
-	{
-	  i_first_zero = i;
-	  n_zeros = 0;
-	}
-      n_zeros += is_zero;
-      if ((!is_zero && n_zeros > max_n_zeros)
-	  || (i + 1 >= ARRAY_LEN (a->as_u16) && n_zeros > max_n_zeros))
-	{
-	  i_max_n_zero = i_first_zero;
-	  max_n_zeros = n_zeros;
-	  i_first_zero = ARRAY_LEN (a->as_u16);
-	  n_zeros = 0;
-	}
-    }
-
-  last_double_colon = 0;
-  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
-    {
-      if (i == i_max_n_zero && max_n_zeros > 1)
-	{
-	  s = format (s, "::");
-	  i += max_n_zeros - 1;
-	  last_double_colon = 1;
-	}
-      else
-	{
-	  s = format (s, "%s%x",
-		      (last_double_colon || i == 0) ? "" : ":",
-		      clib_net_to_host_u16 (a->as_u16[i]));
-	  last_double_colon = 0;
-	}
-    }
-
-  return s;
-}
-
-/* Format an IP46 address. */
-u8 *
-format_ip46_address (u8 * s, va_list * args)
-{
-  ip46_address_t *ip46 = va_arg (*args, ip46_address_t *);
-  ip46_type_t type = va_arg (*args, ip46_type_t);
-  int is_ip4 = 1;
-
-  switch (type)
-    {
-    case IP46_TYPE_ANY:
-      is_ip4 = ip46_address_is_ip4 (ip46);
-      break;
-    case IP46_TYPE_IP4:
-      is_ip4 = 1;
-      break;
-    case IP46_TYPE_IP6:
-      is_ip4 = 0;
-      break;
-    }
-
-  return is_ip4 ?
-    format (s, "%U", format_ip4_address, &ip46->ip4) :
-    format (s, "%U", format_ip6_address, &ip46->ip6);
-}
-
-u8 *
 format_quic_echo_state (u8 * s, va_list * args)
 {
   u32 state = va_arg (*args, u32);
@@ -359,6 +43,8 @@ format_quic_echo_state (u8 * s, va_list * args)
     return format (s, "STATE_LISTEN");
   if (state == STATE_READY)
     return format (s, "STATE_READY");
+  if (state == STATE_DATA_DONE)
+    return format (s, "STATE_DATA_DONE");
   if (state == STATE_DISCONNECTED)
     return format (s, "STATE_DISCONNECTED");
   if (state == STATE_DETACHED)
@@ -367,22 +53,6 @@ format_quic_echo_state (u8 * s, va_list * args)
     return format (s, "unknown state");
 }
 
-static u8 *
-format_api_error (u8 * s, va_list * args)
-{
-  echo_main_t *em = &echo_main;
-  i32 error = va_arg (*args, u32);
-  uword *p;
-
-  p = hash_get (em->error_string_by_error_number, -error);
-
-  if (p)
-    s = format (s, "%s", p[0]);
-  else
-    s = format (s, "%d", error);
-  return s;
-}
-
 static uword
 unformat_close (unformat_input_t * input, va_list * args)
 {
@@ -399,34 +69,9 @@ unformat_close (unformat_input_t * input, va_list * args)
 }
 
 static uword
-unformat_data (unformat_input_t * input, va_list * args)
-{
-  u64 _a;
-  u64 *a = va_arg (*args, u64 *);
-  if (unformat (input, "%lluGb", &_a))
-    {
-      *a = _a << 30;
-      return 1;
-    }
-  else if (unformat (input, "%lluMb", &_a))
-    {
-      *a = _a << 20;
-      return 1;
-    }
-  else if (unformat (input, "%lluKb", &_a))
-    {
-      *a = _a << 10;
-      return 1;
-    }
-  else if (unformat (input, "%llu", a))
-    return 1;
-  return 0;
-}
-
-static uword
 echo_unformat_timing_event (unformat_input_t * input, va_list * args)
 {
-  echo_test_evt_t *a = va_arg (*args, echo_test_evt_t *);
+  u8 *a = va_arg (*args, u8 *);
   if (unformat (input, "start"))
     *a = ECHO_EVT_START;
   else if (unformat (input, "qconnected"))
@@ -468,34 +113,107 @@ echo_format_timing_event (u8 * s, va_list * args)
     return format (s, "unknown timing event");
 }
 
-static void
-init_error_string_table (echo_main_t * em)
-{
-  em->error_string_by_error_number = hash_create (0, sizeof (uword));
-
-#define _(n,v,s) hash_set (em->error_string_by_error_number, -v, s);
-  foreach_vnet_api_error;
-#undef _
-
-  hash_set (em->error_string_by_error_number, 99, "Misc");
-}
-
 /*
  *
  *  End of format functions
  *
  */
 
-static echo_session_t *
-echo_session_alloc (echo_main_t * em)
+static void
+echo_session_prealloc (echo_main_t * em)
 {
+  /* We need to prealloc to avoid vec resize in threads */
   echo_session_t *session;
-  pool_get (em->sessions, session);
-  clib_memset (session, 0, sizeof (*session));
-  session->session_index = session - em->sessions;
-  session->listener_index = SESSION_INVALID_INDEX;
-  session->session_state = QUIC_SESSION_STATE_INITIAL;
-  return session;
+  int n_sessions = em->n_clients * (em->n_stream_clients + 1)
+    + em->i_am_master;
+  int i;
+  for (i = 0; i < n_sessions; i++)
+    {
+      pool_get (em->sessions, session);
+      clib_memset (session, 0, sizeof (*session));
+      session->session_index = session - em->sessions;
+      session->listener_index = SESSION_INVALID_INDEX;
+      session->session_state = QUIC_SESSION_STATE_INITIAL;
+    }
+}
+
+static echo_session_t *
+echo_session_new (echo_main_t * em)
+{
+  /* thread safe new prealloced session */
+  return pool_elt_at_index (em->sessions,
+			    clib_atomic_fetch_add (&em->nxt_available_sidx,
+						   1));
+}
+
+
+static int
+echo_send_rpc (echo_main_t * em, void *fp, void *arg, u32 opaque)
+{
+  svm_msg_q_msg_t msg;
+  echo_rpc_msg_t *evt;
+  if (PREDICT_FALSE (svm_msg_q_lock (em->rpc_msq_queue)))
+    {
+      ECHO_LOG (1, "RPC lock failed");
+      return -1;
+    }
+  if (PREDICT_FALSE (svm_msg_q_ring_is_full (em->rpc_msq_queue, 0)))
+    {
+      svm_msg_q_unlock (em->rpc_msq_queue);
+      ECHO_LOG (1, "RPC ring is full");
+      return -2;
+    }
+  msg = svm_msg_q_alloc_msg_w_ring (em->rpc_msq_queue, 0);
+  if (PREDICT_FALSE (svm_msg_q_msg_is_invalid (&msg)))
+    {
+      ECHO_LOG (1, "RPC msg is invalid");
+      svm_msg_q_unlock (em->rpc_msq_queue);
+      return -2;
+    }
+  evt = (echo_rpc_msg_t *) svm_msg_q_msg_data (em->rpc_msq_queue, &msg);
+  evt->arg = arg;
+  evt->opaque = opaque;
+  evt->fp = fp;
+
+  svm_msg_q_add_and_unlock (em->rpc_msq_queue, &msg);
+  return 0;
+}
+
+static inline void
+echo_segment_handle_add_del (echo_main_t * em, u64 segment_handle, u8 add)
+{
+  clib_spinlock_lock (&em->segment_handles_lock);
+  if (add)
+    hash_set (em->shared_segment_handles, segment_handle, 1);
+  else
+    hash_unset (em->shared_segment_handles, segment_handle);
+  clib_spinlock_unlock (&em->segment_handles_lock);
+}
+
+static inline void
+echo_session_handle_add_del (echo_main_t * em, u64 handle, u32 sid)
+{
+  clib_spinlock_lock (&em->sid_vpp_handles_lock);
+  if (sid == SESSION_INVALID_INDEX)
+    hash_unset (em->session_index_by_vpp_handles, handle);
+  else
+    hash_set (em->session_index_by_vpp_handles, handle, sid);
+  clib_spinlock_unlock (&em->sid_vpp_handles_lock);
+}
+
+static inline echo_session_t *
+echo_get_session_from_handle (echo_main_t * em, u64 handle)
+{
+  uword *p;
+  clib_spinlock_lock (&em->sid_vpp_handles_lock);
+  p = hash_get (em->session_index_by_vpp_handles, handle);
+  clib_spinlock_unlock (&em->sid_vpp_handles_lock);
+  if (!p)
+    {
+      ECHO_FAIL ("unknown handle 0x%lx", handle);
+      return 0;
+    }
+  return pool_elt_at_index (em->sessions, p[0]);
 }
 
 /*
@@ -596,12 +314,12 @@ server_send_unbind (echo_main_t * em)
 }
 
 static void
-echo_send_connect (echo_main_t * em, u8 * uri, u32 opaque)
+echo_send_connect (u8 * uri, u32 opaque)
 {
+  echo_main_t *em = &echo_main;
   vl_api_connect_uri_t *cmp;
   cmp = vl_msg_api_alloc (sizeof (*cmp));
   clib_memset (cmp, 0, sizeof (*cmp));
-
   cmp->_vl_msg_id = ntohs (VL_API_CONNECT_URI);
   cmp->client_index = em->my_client_index;
   cmp->context = ntohl (opaque);
@@ -610,8 +328,9 @@ echo_send_connect (echo_main_t * em, u8 * uri, u32 opaque)
 }
 
 static void
-echo_disconnect_session (echo_main_t * em, echo_session_t * s)
+echo_disconnect_session (echo_session_t * s, u32 opaque)
 {
+  echo_main_t *em = &echo_main;
   vl_api_disconnect_session_t *dmp;
   dmp = vl_msg_api_alloc (sizeof (*dmp));
   clib_memset (dmp, 0, sizeof (*dmp));
@@ -653,37 +372,39 @@ wait_for_segment_allocation (u64 segment_handle)
 static void
 quic_echo_notify_event (echo_main_t * em, echo_test_evt_t e)
 {
-  if (em->events_sent & e)
+  if (em->timing.events_sent & e)
     return;
-  if (em->timing_start_event == e)
-    em->start_time = clib_time_now (&em->clib_time);
-  else if (em->timing_end_event == e)
-    em->end_time = clib_time_now (&em->clib_time);
-  em->events_sent |= e;
+  if (em->timing.start_event == e)
+    em->timing.start_time = clib_time_now (&em->clib_time);
+  else if (em->timing.end_event == e)
+    em->timing.end_time = clib_time_now (&em->clib_time);
+  em->timing.events_sent |= e;
 }
 
 static void
 echo_assert_test_suceeded (echo_main_t * em)
 {
-  CHECK (em->rx_total,
-	 em->n_stream_clients * em->n_clients * em->bytes_to_receive,
-	 "Not enough data received");
-  CHECK (em->tx_total,
-	 em->n_stream_clients * em->n_clients * em->bytes_to_send,
-	 "Not enough data sent");
+  CHECK (em->n_stream_clients * em->n_clients * em->bytes_to_receive,
+	 em->stats.rx_total, "Not enough data received");
+  CHECK (em->n_stream_clients * em->n_clients * em->bytes_to_send,
+	 em->stats.tx_total, "Not enough data sent");
+  clib_spinlock_lock (&em->sid_vpp_handles_lock);
   CHECK (0, hash_elts (em->session_index_by_vpp_handles),
 	 "Some sessions are still open");
+  clib_spinlock_unlock (&em->sid_vpp_handles_lock);
 }
 
 always_inline void
 echo_session_dequeue_notify (echo_session_t * s)
 {
   int rv;
-  rv = app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo->master_session_index,
-			       SESSION_IO_EVT_RX, SVM_Q_WAIT);
-  svm_fifo_clear_deq_ntf (s->rx_fifo);
-  if (rv)
+  if (!svm_fifo_set_event (s->rx_fifo))
+    return;
+  if ((rv =
+       app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo->master_session_index,
+			       SESSION_IO_EVT_RX, SVM_Q_WAIT)))
     ECHO_FAIL ("app_send_io_evt_to_vpp errored %d", rv);
+  svm_fifo_clear_deq_ntf (s->rx_fifo);
 }
 
 static int
@@ -709,17 +430,8 @@ ssvm_segment_attach (char *name, ssvm_segment_type_t type, int fd)
 static void
 stop_signal (int signum)
 {
-  echo_main_t *um = &echo_main;
-  um->time_to_stop = 1;
-}
-
-static clib_error_t *
-setup_signal_handlers (void)
-{
-  signal (SIGINT, stop_signal);
-  signal (SIGQUIT, stop_signal);
-  signal (SIGTERM, stop_signal);
-  return 0;
+  echo_main_t *em = &echo_main;
+  em->time_to_stop = 1;
 }
 
 int
@@ -778,21 +490,31 @@ echo_event_didnt_happen (u8 e)
 static void
 print_global_json_stats (echo_main_t * em)
 {
-  if (!(em->events_sent & em->timing_start_event))
-    return echo_event_didnt_happen (em->timing_start_event);
-  if (!(em->events_sent & em->timing_end_event))
-    return echo_event_didnt_happen (em->timing_end_event);
-  f64 deltat = em->end_time - em->start_time;
+  if (!(em->timing.events_sent & em->timing.start_event))
+    return echo_event_didnt_happen (em->timing.start_event);
+  if (!(em->timing.events_sent & em->timing.end_event))
+    return echo_event_didnt_happen (em->timing.end_event);
+  f64 deltat = em->timing.end_time - em->timing.start_time;
   u8 *start_evt =
-    format (0, "%U", echo_format_timing_event, em->timing_start_event);
+    format (0, "%U", echo_format_timing_event, em->timing.start_event);
   u8 *end_evt =
-    format (0, "%U", echo_format_timing_event, em->timing_end_event);
+    format (0, "%U", echo_format_timing_event, em->timing.end_event);
   fformat (stdout, "{\n");
   fformat (stdout, "\"time\": \"%.9f\",\n", deltat);
   fformat (stdout, "\"start_evt\": \"%s\",\n", start_evt);
   fformat (stdout, "\"end_evt\": \"%s\",\n", end_evt);
-  fformat (stdout, "\"rx_data\": %lld,\n", em->rx_total);
-  fformat (stdout, "\"tx_rx\": %lld,\n", em->tx_total);
+  fformat (stdout, "\"rx_data\": %lld,\n", em->stats.rx_total);
+  fformat (stdout, "\"tx_rx\": %lld,\n", em->stats.tx_total);
+  fformat (stdout, "\"closing\": {\n");
+  fformat (stdout, "  \"reset\": { \"q\": %d, \"s\": %d },\n",
+	   em->stats.reset_count.q, em->stats.reset_count.s);
+  fformat (stdout, "  \"close\": { \"q\": %d, \"s\": %d },\n",
+	   em->stats.close_count.q, em->stats.close_count.s);
+  fformat (stdout, "  \"active\": { \"q\": %d, \"s\": %d },\n",
+	   em->stats.active_count.q, em->stats.active_count.s);
+  fformat (stdout, "  \"clean\": { \"q\": %d, \"s\": %d }\n",
+	   em->stats.clean_count.q, em->stats.clean_count.s);
+  fformat (stdout, "}\n");
   fformat (stdout, "}\n");
 }
 
@@ -800,26 +522,36 @@ static void
 print_global_stats (echo_main_t * em)
 {
   u8 *s;
-  if (!(em->events_sent & em->timing_start_event))
-    return echo_event_didnt_happen (em->timing_start_event);
-  if (!(em->events_sent & em->timing_end_event))
-    return echo_event_didnt_happen (em->timing_end_event);
-  f64 deltat = em->end_time - em->start_time;
+  if (!(em->timing.events_sent & em->timing.start_event))
+    return echo_event_didnt_happen (em->timing.start_event);
+  if (!(em->timing.events_sent & em->timing.end_event))
+    return echo_event_didnt_happen (em->timing.end_event);
+  f64 deltat = em->timing.end_time - em->timing.start_time;
   s = format (0, "%U:%U",
-	      echo_format_timing_event, em->timing_start_event,
-	      echo_format_timing_event, em->timing_end_event);
+	      echo_format_timing_event, em->timing.start_event,
+	      echo_format_timing_event, em->timing.end_event);
   fformat (stdout, "Timing %s\n", s);
   fformat (stdout, "-------- TX --------\n");
   fformat (stdout, "%lld bytes (%lld mbytes, %lld gbytes) in %.6f seconds\n",
-	   em->tx_total, em->tx_total / (1ULL << 20),
-	   em->tx_total / (1ULL << 30), deltat);
-  fformat (stdout, "%.4f Gbit/second\n", (em->tx_total * 8.0) / deltat / 1e9);
+	   em->stats.tx_total, em->stats.tx_total / (1ULL << 20),
+	   em->stats.tx_total / (1ULL << 30), deltat);
+  fformat (stdout, "%.4f Gbit/second\n",
+	   (em->stats.tx_total * 8.0) / deltat / 1e9);
   fformat (stdout, "-------- RX --------\n");
   fformat (stdout, "%lld bytes (%lld mbytes, %lld gbytes) in %.6f seconds\n",
-	   em->rx_total, em->rx_total / (1ULL << 20),
-	   em->rx_total / (1ULL << 30), deltat);
-  fformat (stdout, "%.4f Gbit/second\n", (em->rx_total * 8.0) / deltat / 1e9);
+	   em->stats.rx_total, em->stats.rx_total / (1ULL << 20),
+	   em->stats.rx_total / (1ULL << 30), deltat);
+  fformat (stdout, "%.4f Gbit/second\n",
+	   (em->stats.rx_total * 8.0) / deltat / 1e9);
   fformat (stdout, "--------------------\n");
+  fformat (stdout, "Received close on %dQ %dS\n", em->stats.close_count.q,
+	   em->stats.close_count.s);
+  fformat (stdout, "Received reset on %dQ %dS\n", em->stats.reset_count.q,
+	   em->stats.reset_count.s);
+  fformat (stdout, "Sent close on     %dQ %dS\n", em->stats.active_count.q,
+	   em->stats.active_count.s);
+  fformat (stdout, "Discarded         %dQ %dS\n", em->stats.clean_count.q,
+	   em->stats.clean_count.s);
 }
 
 static void
@@ -840,7 +572,8 @@ echo_free_sessions (echo_main_t * em)
   {
     /* Free session */
     s = pool_elt_at_index (em->sessions, *session_index);
-    ECHO_LOG (1, "Freeing session 0x%lx", s->vpp_session_handle);
+    echo_session_handle_add_del (em, s->vpp_session_handle,
+				 SESSION_INVALID_INDEX);
     pool_put (em->sessions, s);
     clib_memset (s, 0xfe, sizeof (*s));
   }
@@ -849,46 +582,37 @@ echo_free_sessions (echo_main_t * em)
 static void
 echo_cleanup_session (echo_main_t * em, echo_session_t * s)
 {
-  u64 c;
   echo_session_t *ls;
-  if (s->listener_index != SESSION_INVALID_INDEX)
+  ASSERT (s->session_state < QUIC_SESSION_STATE_CLOSED);
+  if (s->session_type == QUIC_SESSION_TYPE_QUIC)
+    {
+      clib_atomic_sub_fetch (&em->n_quic_clients_connected, 1);
+    }
+  else if (s->session_type == QUIC_SESSION_TYPE_STREAM)
     {
       ls = pool_elt_at_index (em->sessions, s->listener_index);
-      c = clib_atomic_sub_fetch (&ls->accepted_session_count, 1);
-      if (c == 0 && ls->session_type == QUIC_SESSION_TYPE_QUIC)
+      ASSERT (ls->session_type == QUIC_SESSION_TYPE_QUIC);
+      if (!clib_atomic_sub_fetch (&ls->accepted_session_count, 1))
 	{
 	  if (em->send_quic_disconnects == ECHO_CLOSE_F_ACTIVE)
-	    echo_disconnect_session (em, ls);
+	    {
+	      echo_send_rpc (em, echo_disconnect_session, (void *) ls, 0);
+	      em->stats.active_count.q++;
+	    }
 	  else if (em->send_quic_disconnects == ECHO_CLOSE_F_NONE)
-	    echo_cleanup_session (em, ls);
+	    {
+	      echo_cleanup_session (em, ls);
+	      em->stats.clean_count.q++;
+	    }
 	}
+      clib_atomic_sub_fetch (&em->n_clients_connected, 1);
     }
-  if (s->session_type == QUIC_SESSION_TYPE_QUIC)
-    clib_atomic_sub_fetch (&em->n_quic_clients_connected, 1);
-  else if (s->session_type == QUIC_SESSION_TYPE_STREAM)
-    clib_atomic_sub_fetch (&em->n_clients_connected, 1);
-
   ECHO_LOG (1, "Cleanup sessions (still %uQ %uS)",
 	    em->n_quic_clients_connected, em->n_clients_connected);
-  hash_unset (em->session_index_by_vpp_handles, s->vpp_session_handle);
   s->session_state = QUIC_SESSION_STATE_CLOSED;
 }
 
 static void
-echo_initiate_session_close (echo_main_t * em, echo_session_t * s, u8 active)
-{
-  if (s->session_type == QUIC_SESSION_TYPE_STREAM)
-    {
-      if (!active && s->bytes_to_receive)
-	s->session_state = QUIC_SESSION_STATE_AWAIT_DATA;
-      else
-	s->session_state = QUIC_SESSION_STATE_CLOSING;
-    }
-  else
-    echo_cleanup_session (em, s);	/* We can clean Q/Lsessions right away */
-}
-
-static void
 echo_initiate_qsession_close_no_stream (echo_main_t * em)
 {
   ECHO_LOG (1, "Closing Qsessions");
@@ -898,16 +622,23 @@ echo_initiate_qsession_close_no_stream (echo_main_t * em)
   /* *INDENT-OFF* */
   pool_foreach (s, em->sessions,
   ({
-    if (s->session_type == QUIC_SESSION_TYPE_QUIC && s->accepted_session_count == 0)
+    if (s->session_type == QUIC_SESSION_TYPE_QUIC)
       {
 	ECHO_LOG (1,"ACTIVE close 0x%lx", s->vpp_session_handle);
         if (em->send_quic_disconnects == ECHO_CLOSE_F_ACTIVE)
-	  echo_disconnect_session (em, s);
+          {
+	    echo_send_rpc (em, echo_disconnect_session, (void *) s, 0);
+	    em->stats.active_count.q++;
+          }
 	else if (em->send_quic_disconnects == ECHO_CLOSE_F_NONE)
-	  echo_cleanup_session (em, s);
+	  {
+	    echo_cleanup_session (em, s);
+	    em->stats.clean_count.q++;
+	  }
       }
   }));
   /* *INDENT-ON* */
+  em->state = STATE_DATA_DONE;
 }
 
 static void
@@ -975,23 +706,54 @@ mirror_data_chunk (echo_main_t * em, echo_session_t * s, u8 * tx_buf, u64 len)
   return n_sent;
 }
 
+static void
+echo_update_count_on_session_close (echo_main_t * em, echo_session_t * s)
+{
+
+  ECHO_LOG (1, "[%lu/%lu] -> S(%x) -> [%lu/%lu]",
+	    s->bytes_received, s->bytes_received + s->bytes_to_receive,
+	    s->session_index, s->bytes_sent,
+	    s->bytes_sent + s->bytes_to_send);
+  clib_atomic_fetch_add (&em->stats.tx_total, s->bytes_sent);
+  clib_atomic_fetch_add (&em->stats.rx_total, s->bytes_received);
+
+  if (PREDICT_FALSE (em->stats.rx_total ==
+		     em->n_clients * em->n_stream_clients *
+		     em->bytes_to_receive))
+    quic_echo_notify_event (em, ECHO_EVT_LAST_BYTE);
+}
+
+static inline void
+echo_check_closed_listener (echo_main_t * em, echo_session_t * s)
+{
+  echo_session_t *ls;
+  /* if parent has died, terminate gracefully */
+  ls = pool_elt_at_index (em->sessions, s->listener_index);
+  if (ls->session_state < QUIC_SESSION_STATE_CLOSING)
+    return;
+  ECHO_LOG (2, "Session 0%lx died, close child 0x%lx", ls->vpp_session_handle,
+	    s->vpp_session_handle);
+  clib_atomic_sub_fetch (&em->n_clients_connected, 1);
+  em->stats.clean_count.s++;
+  echo_update_count_on_session_close (em, s);
+  s->session_state = QUIC_SESSION_STATE_CLOSED;
+}
+
 /*
  * Rx/Tx polling thread per connection
  */
 static void
-echo_thread_handle_data (echo_main_t * em, echo_session_t * s, u8 * rx_buf)
+echo_handle_data (echo_main_t * em, echo_session_t * s, u8 * rx_buf)
 {
-  int n_read, n_sent;
+  int n_read, n_sent = 0;
 
   n_read = recv_data_chunk (em, s, rx_buf);
   if (em->data_source == ECHO_TEST_DATA_SOURCE)
-    n_sent =
-      send_data_chunk (s, em->connect_test_data,
-		       s->bytes_sent % em->tx_buf_size, em->tx_buf_size);
+    n_sent = send_data_chunk (s, em->connect_test_data,
+			      s->bytes_sent % em->tx_buf_size,
+			      em->tx_buf_size);
   else if (em->data_source == ECHO_RX_DATA_SOURCE)
     n_sent = mirror_data_chunk (em, s, rx_buf, n_read);
-  else
-    n_sent = 0;
   if (!s->bytes_to_send && !s->bytes_to_receive)
     {
       /* Session is done, need to close */
@@ -1001,16 +763,22 @@ echo_thread_handle_data (echo_main_t * em, echo_session_t * s, u8 * rx_buf)
 	{
 	  s->session_state = QUIC_SESSION_STATE_AWAIT_CLOSING;
 	  if (em->send_stream_disconnects == ECHO_CLOSE_F_ACTIVE)
-	    echo_disconnect_session (em, s);
+	    {
+	      echo_send_rpc (em, echo_disconnect_session, (void *) s, 0);
+	      em->stats.close_count.s++;
+	    }
 	  else if (em->send_stream_disconnects == ECHO_CLOSE_F_NONE)
-	    s->session_state = QUIC_SESSION_STATE_CLOSING;
+	    {
+	      s->session_state = QUIC_SESSION_STATE_CLOSING;
+	      em->stats.clean_count.s++;
+	    }
 	}
       return;
     }
 
+  /* Check for idle clients */
   if (em->log_lvl > 1)
     {
-      /* check idle clients */
       if (n_sent || n_read)
 	s->idle_cycles = 0;
       else if (s->idle_cycles++ == 1e7)
@@ -1018,37 +786,24 @@ echo_thread_handle_data (echo_main_t * em, echo_session_t * s, u8 * rx_buf)
 	  s->idle_cycles = 0;
 	  ECHO_LOG (1, "Idle client TX:%dB RX:%dB", s->bytes_to_send,
 		    s->bytes_to_receive);
-	  ECHO_LOG (1, "Idle FIFOs  TX:%dB RX:%dB",
+	  ECHO_LOG (1, "Idle FIFOs TX:%dB RX:%dB",
 		    svm_fifo_max_dequeue (s->tx_fifo),
 		    svm_fifo_max_dequeue (s->rx_fifo));
+	  ECHO_LOG (1, "Session 0x%lx state %u", s->vpp_session_handle,
+		    s->session_state);
 	}
     }
 }
 
-static void
-echo_thread_handle_closing (echo_main_t * em, echo_session_t * s)
-{
-
-  ECHO_LOG (1, "[%lu/%lu] -> S(%x) -> [%lu/%lu]",
-	    s->bytes_received, s->bytes_received + s->bytes_to_receive,
-	    s->session_index, s->bytes_sent,
-	    s->bytes_sent + s->bytes_to_send);
-  clib_atomic_fetch_add (&em->tx_total, s->bytes_sent);
-  clib_atomic_fetch_add (&em->rx_total, s->bytes_received);
-
-  if (PREDICT_FALSE (em->rx_total ==
-		     em->n_clients * em->n_stream_clients *
-		     em->bytes_to_receive))
-    quic_echo_notify_event (em, ECHO_EVT_LAST_BYTE);
-  echo_cleanup_session (em, s);
-}
-
 static void *
-echo_thread_fn (void *arg)
+echo_data_thread_fn (void *arg)
 {
+  clib_mem_set_thread_index ();
   echo_main_t *em = &echo_main;
-  u32 thread_n_sessions = (u64) arg & 0xFFFFFFFF;
-  u32 session_first_idx = (u64) arg >> 32;
+  u32 N = em->n_clients * em->n_stream_clients;
+  u32 n = (N + em->n_rx_threads - 1) / em->n_rx_threads;
+  u32 idx = (u64) arg;
+  u32 thread_n_sessions = clib_min (n, N - n * idx);
 
   u32 i = 0;
   u32 n_closed_sessions = 0;
@@ -1057,59 +812,37 @@ echo_thread_fn (void *arg)
   echo_session_t *s;
   vec_validate (rx_buf, em->rx_buf_size);
 
-  while (!em->time_to_stop && em->state != STATE_READY)
-    ;
-
-  for (i = 0; !em->time_to_stop; i++)
+  for (i = 0; !em->time_to_stop; i = (i + 1) % thread_n_sessions)
     {
-      if (i % thread_n_sessions == 0)
-	n_closed_sessions = 0;
-      session_index =
-	em->thread_args[session_first_idx + i % thread_n_sessions];
+      n_closed_sessions = i == 0 ? 0 : n_closed_sessions;
+      session_index = em->data_thread_args[n * idx + i];
+      if (session_index == SESSION_INVALID_INDEX)
+	continue;
       s = pool_elt_at_index (em->sessions, session_index);
-      if (s->session_state == QUIC_SESSION_STATE_INITIAL
-	  || s->session_state == QUIC_SESSION_STATE_AWAIT_DATA)
-	echo_thread_handle_data (em, s, rx_buf);
-      else if (s->session_state == QUIC_SESSION_STATE_CLOSING)
-	echo_thread_handle_closing (em, s);
-      else if (s->session_state == QUIC_SESSION_STATE_CLOSED)
-	n_closed_sessions++;
+      switch (s->session_state)
+	{
+	case QUIC_SESSION_STATE_READY:
+	case QUIC_SESSION_STATE_AWAIT_DATA:
+	  echo_handle_data (em, s, rx_buf);
+	  echo_check_closed_listener (em, s);
+	  break;
+	case QUIC_SESSION_STATE_AWAIT_CLOSING:
+	  echo_check_closed_listener (em, s);
+	  break;
+	case QUIC_SESSION_STATE_CLOSING:
+	  echo_update_count_on_session_close (em, s);
+	  echo_cleanup_session (em, s);
+	  break;
+	case QUIC_SESSION_STATE_CLOSED:
+	  n_closed_sessions++;
+	  break;
+	}
       if (n_closed_sessions == thread_n_sessions)
 	break;
     }
   pthread_exit (0);
 }
 
-static int
-echo_start_rx_thread (u32 session_index)
-{
-  /* Each thread owns n consecutive sessions of the total N */
-
-  echo_main_t *em = &echo_main;
-  u32 N = em->n_clients * em->n_stream_clients;
-  u32 nc, n, first_idx, thread_sessions;
-
-  n = (N + em->n_rx_threads - 1) / em->n_rx_threads;
-  nc = em->n_clients_connected;
-
-  ASSERT (nc + 1 <= N);
-  em->thread_args[nc] = session_index;
-
-  if ((nc + 1) % n == 0 || nc + 1 == N)
-    {
-      first_idx = n * (nc / n);
-      thread_sessions = (nc + 1) % n == 0 ? n : (nc + 1) % n;
-      ECHO_LOG (1, "Start thread %u [%u -> %u]", nc / n, first_idx,
-		first_idx + thread_sessions - 1);
-      return pthread_create (&em->client_thread_handles[nc / n],
-			     NULL /*attr */ , echo_thread_fn,
-			     (void *) ((u64) first_idx << 32 | (u64)
-				       thread_sessions));
-    }
-
-  return 0;
-}
-
 static void
 session_bound_handler (session_bound_msg_t * mp)
 {
@@ -1126,11 +859,9 @@ session_bound_handler (session_bound_msg_t * mp)
 	    clib_net_to_host_u16 (mp->lcl_port));
 
   /* Allocate local session and set it up */
-  listen_session = echo_session_alloc (em);
+  listen_session = echo_session_new (em);
   listen_session->session_type = QUIC_SESSION_TYPE_LISTEN;
-  listen_session->accepted_session_count = 0;
-  hash_set (em->session_index_by_vpp_handles, mp->handle,
-	    listen_session->session_index);
+  echo_session_handle_add_del (em, mp->handle, listen_session->session_index);
   em->state = STATE_LISTEN;
   em->listen_session_index = listen_session->session_index;
 }
@@ -1142,10 +873,9 @@ session_accepted_handler (session_accepted_msg_t * mp)
   session_accepted_reply_msg_t *rmp;
   svm_fifo_t *rx_fifo, *tx_fifo;
   echo_main_t *em = &echo_main;
-  echo_session_t *session, *listen_session;
-  uword *p;
+  echo_session_t *session, *ls;
   /* Allocate local session and set it up */
-  session = echo_session_alloc (em);
+  session = echo_session_new (em);
 
   if (wait_for_segment_allocation (mp->segment_handle))
     {
@@ -1164,23 +894,14 @@ session_accepted_handler (session_accepted_msg_t * mp)
   session->start = clib_time_now (&em->clib_time);
   session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
 					 svm_msg_q_t *);
-
-  session->accepted_session_count = 0;
-  p = hash_get (em->session_index_by_vpp_handles, mp->listener_handle);
-  if (!p)
-    {
-      ECHO_FAIL ("unknown handle 0x%lx", mp->listener_handle);
-      return;
-    }
-  session->listener_index = p[0];
-  listen_session = pool_elt_at_index (em->sessions, p[0]);
-  clib_atomic_fetch_add (&listen_session->accepted_session_count, 1);
+  if (!(ls = echo_get_session_from_handle (em, mp->listener_handle)))
+    return;
+  session->listener_index = ls->session_index;
 
   /* Add it to lookup table */
   ECHO_LOG (1, "Accepted session 0x%lx -> 0x%lx", mp->handle,
 	    mp->listener_handle);
-  hash_set (em->session_index_by_vpp_handles, mp->handle,
-	    session->session_index);
+  echo_session_handle_add_del (em, mp->handle, session->session_index);
 
   app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
 			     SESSION_CTRL_EVT_ACCEPTED_REPLY);
@@ -1189,46 +910,37 @@ session_accepted_handler (session_accepted_msg_t * mp)
   rmp->context = mp->context;
   app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
 
-  if (listen_session->session_type == QUIC_SESSION_TYPE_LISTEN)
+  if (ls->session_type == QUIC_SESSION_TYPE_LISTEN)
     {
       quic_echo_notify_event (em, ECHO_EVT_FIRST_QCONNECT);
       session->session_type = QUIC_SESSION_TYPE_QUIC;
+      session->accepted_session_count = 0;
       if (em->cb_vft.quic_accepted_cb)
 	em->cb_vft.quic_accepted_cb (mp, session->session_index);
       clib_atomic_fetch_add (&em->n_quic_clients_connected, 1);
     }
-  else if (em->i_am_master)
-    {
-      session->session_type = QUIC_SESSION_TYPE_STREAM;
-      quic_echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
-      if (em->cb_vft.server_stream_accepted_cb)
-	em->cb_vft.server_stream_accepted_cb (mp, session->session_index);
-      clib_atomic_fetch_add (&em->n_clients_connected, 1);
-    }
   else
     {
       session->session_type = QUIC_SESSION_TYPE_STREAM;
       quic_echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
-      if (em->cb_vft.client_stream_accepted_cb)
+      clib_atomic_fetch_add (&ls->accepted_session_count, 1);
+      if (em->i_am_master && em->cb_vft.server_stream_accepted_cb)
+	em->cb_vft.server_stream_accepted_cb (mp, session->session_index);
+      if (!em->i_am_master && em->cb_vft.client_stream_accepted_cb)
 	em->cb_vft.client_stream_accepted_cb (mp, session->session_index);
       clib_atomic_fetch_add (&em->n_clients_connected, 1);
     }
 
   if (em->n_clients_connected == em->n_clients * em->n_stream_clients
       && em->n_clients_connected != 0)
-    {
-      ECHO_LOG (1, "App is ready");
-      em->state = STATE_READY;
-      quic_echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
-    }
-  if (em->n_quic_clients_connected == em->n_clients)
+    quic_echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
+  if (em->n_quic_clients_connected == em->n_clients
+      && em->state < STATE_READY)
     {
       quic_echo_notify_event (em, ECHO_EVT_LAST_QCONNECTED);
+      em->state = STATE_READY;
       if (em->n_stream_clients == 0)
-	{
-	  em->state = STATE_READY;
-	  echo_initiate_qsession_close_no_stream (em);
-	}
+	echo_initiate_qsession_close_no_stream (em);
     }
 }
 
@@ -1247,7 +959,7 @@ session_connected_handler (session_connected_msg_t * mp)
       return;
     }
 
-  session = echo_session_alloc (em);
+  session = echo_session_new (em);
   if (wait_for_segment_allocation (mp->segment_handle))
     {
       ECHO_FAIL ("wait_for_segment_allocation errored");
@@ -1266,58 +978,42 @@ session_connected_handler (session_connected_msg_t * mp)
   session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
 					 svm_msg_q_t *);
 
-  session->accepted_session_count = 0;
-  if (listener_index != SESSION_INVALID_INDEX)
-    {
-      listen_session = pool_elt_at_index (em->sessions, listener_index);
-      clib_atomic_fetch_add (&listen_session->accepted_session_count, 1);
-      session->listener_index = listen_session->session_index;
-    }
-
-  ECHO_LOG (1, "Connected session 0x%lx -> 0x%lx", mp->handle,
-	    listener_index !=
-	    SESSION_INVALID_INDEX ? listen_session->vpp_session_handle : (u64)
-	    ~ 0);
-  hash_set (em->session_index_by_vpp_handles, mp->handle,
-	    session->session_index);
+  echo_session_handle_add_del (em, mp->handle, session->session_index);
 
   if (listener_index == SESSION_INVALID_INDEX)
     {
+      ECHO_LOG (1, "Connected session 0x%lx -> URI", mp->handle);
       session->session_type = QUIC_SESSION_TYPE_QUIC;
+      session->accepted_session_count = 0;
       if (em->cb_vft.quic_connected_cb)
 	em->cb_vft.quic_connected_cb (mp, session->session_index);
       clib_atomic_fetch_add (&em->n_quic_clients_connected, 1);
     }
-  else if (em->i_am_master)
-    {
-      session->session_type = QUIC_SESSION_TYPE_STREAM;
-      if (em->cb_vft.server_stream_connected_cb)
-	em->cb_vft.server_stream_connected_cb (mp, session->session_index);
-      clib_atomic_fetch_add (&em->n_clients_connected, 1);
-    }
   else
     {
+      listen_session = pool_elt_at_index (em->sessions, listener_index);
+      session->listener_index = listener_index;
+      ECHO_LOG (1, "Connected session 0x%lx -> 0x%lx", mp->handle,
+		listen_session->vpp_session_handle);
       session->session_type = QUIC_SESSION_TYPE_STREAM;
-      if (em->cb_vft.client_stream_connected_cb)
+      clib_atomic_fetch_add (&listen_session->accepted_session_count, 1);
+      if (em->i_am_master && em->cb_vft.server_stream_connected_cb)
+	em->cb_vft.server_stream_connected_cb (mp, session->session_index);
+      if (!em->i_am_master && em->cb_vft.client_stream_connected_cb)
 	em->cb_vft.client_stream_connected_cb (mp, session->session_index);
       clib_atomic_fetch_add (&em->n_clients_connected, 1);
     }
 
   if (em->n_clients_connected == em->n_clients * em->n_stream_clients
       && em->n_clients_connected != 0)
-    {
-      ECHO_LOG (1, "App is ready");
-      em->state = STATE_READY;
-      quic_echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
-    }
-  if (em->n_quic_clients_connected == em->n_clients)
+    quic_echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
+  if (em->n_quic_clients_connected == em->n_clients
+      && em->state < STATE_READY)
     {
       quic_echo_notify_event (em, ECHO_EVT_LAST_QCONNECTED);
+      em->state = STATE_READY;
       if (em->n_stream_clients == 0)
-	{
-	  em->state = STATE_READY;
-	  echo_initiate_qsession_close_no_stream (em);
-	}
+	echo_initiate_qsession_close_no_stream (em);
     }
 }
 
@@ -1337,7 +1033,7 @@ echo_on_connected_connect (session_connected_msg_t * mp, u32 session_index)
 
   quic_echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
   for (i = 0; i < em->n_stream_clients; i++)
-    echo_send_connect (em, uri, session_index);
+    echo_send_rpc (em, echo_send_connect, (void *) uri, session_index);
 
   ECHO_LOG (0, "Qsession 0x%llx connected to %U:%d",
 	    mp->handle, format_ip46_address, &mp->lcl.ip,
@@ -1348,18 +1044,13 @@ static void
 echo_on_connected_send (session_connected_msg_t * mp, u32 session_index)
 {
   echo_main_t *em = &echo_main;
-  int rv;
   echo_session_t *session;
 
   session = pool_elt_at_index (em->sessions, session_index);
   session->bytes_to_send = em->bytes_to_send;
   session->bytes_to_receive = em->bytes_to_receive;
-
-  if ((rv = echo_start_rx_thread (session_index)))
-    {
-      ECHO_FAIL ("pthread_create returned %d", rv);
-      return;
-    }
+  session->session_state = QUIC_SESSION_STATE_READY;
+  em->data_thread_args[em->n_clients_connected] = session->session_index;
 }
 
 static void
@@ -1373,18 +1064,13 @@ static void
 echo_on_accept_recv (session_accepted_msg_t * mp, u32 session_index)
 {
   echo_main_t *em = &echo_main;
-  int rv;
   echo_session_t *session;
 
   session = pool_elt_at_index (em->sessions, session_index);
   session->bytes_to_send = em->bytes_to_send;
   session->bytes_to_receive = em->bytes_to_receive;
-
-  if ((rv = echo_start_rx_thread (session_index)))
-    {
-      ECHO_FAIL ("pthread_create returned %d", rv);
-      return;
-    }
+  em->data_thread_args[em->n_clients_connected] = session->session_index;
+  session->session_state = QUIC_SESSION_STATE_READY;
 }
 
 static void
@@ -1397,7 +1083,7 @@ echo_on_accept_connect (session_accepted_msg_t * mp, u32 session_index)
 
   quic_echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
   for (i = 0; i < em->n_stream_clients; i++)
-    echo_send_connect (em, uri, session_index);
+    echo_send_rpc (em, echo_send_connect, (void *) uri, session_index);
 }
 
 static void
@@ -1467,17 +1153,11 @@ session_disconnected_handler (session_disconnected_msg_t * mp)
   session_disconnected_reply_msg_t *rmp;
   echo_main_t *em = &echo_main;
   echo_session_t *s;
-  uword *p;
   int rv = 0;
   ECHO_LOG (1, "passive close session 0x%lx", mp->handle);
-  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
-  if (!p)
-    {
-      ECHO_FAIL ("couldn't find session key %llx", mp->handle);
-      return;
-    }
+  if (!(s = echo_get_session_from_handle (em, mp->handle)))
+    return;
 
-  s = pool_elt_at_index (em->sessions, p[0]);
   app_alloc_ctrl_evt_to_vpp (s->vpp_evt_q, app_evt,
 			     SESSION_CTRL_EVT_DISCONNECTED_REPLY);
   rmp = (session_disconnected_reply_msg_t *) app_evt->evt->data;
@@ -1486,9 +1166,20 @@ session_disconnected_handler (session_disconnected_msg_t * mp)
   rmp->context = mp->context;
   app_send_ctrl_evt_to_vpp (s->vpp_evt_q, app_evt);
 
-  echo_initiate_session_close (em, s, 0 /* active */ );
   if (s->session_type == QUIC_SESSION_TYPE_STREAM)
-    session_print_stats (em, s);
+    {
+      session_print_stats (em, s);
+      if (s->bytes_to_receive || s->bytes_to_send)
+	s->session_state = QUIC_SESSION_STATE_AWAIT_DATA;
+      else
+	s->session_state = QUIC_SESSION_STATE_CLOSING;
+      em->stats.close_count.s++;
+    }
+  else
+    {
+      echo_cleanup_session (em, s);	/* We can clean Q/Lsessions right away */
+      em->stats.close_count.q++;
+    }
 }
 
 static void
@@ -1497,28 +1188,29 @@ session_reset_handler (session_reset_msg_t * mp)
   app_session_evt_t _app_evt, *app_evt = &_app_evt;
   echo_main_t *em = &echo_main;
   session_reset_reply_msg_t *rmp;
-  echo_session_t *session = 0;
-  uword *p;
+  echo_session_t *s = 0;
   int rv = 0;
 
   ECHO_LOG (1, "Reset session 0x%lx", mp->handle);
-  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
-
-  if (!p)
+  if (!(s = echo_get_session_from_handle (em, mp->handle)))
+    return;
+  if (s->session_type == QUIC_SESSION_TYPE_STREAM)
     {
-      ECHO_FAIL ("couldn't find session key %llx", mp->handle);
-      return;
+      em->stats.reset_count.s++;
+      s->session_state = QUIC_SESSION_STATE_CLOSING;
+    }
+  else
+    {
+      em->stats.reset_count.q++;
+      echo_cleanup_session (em, s);	/* We can clean Q/Lsessions right away */
     }
 
-  session = pool_elt_at_index (em->sessions, p[0]);
-  /* Cleanup later */
-  em->time_to_stop = 1;
-  app_alloc_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt,
+  app_alloc_ctrl_evt_to_vpp (s->vpp_evt_q, app_evt,
 			     SESSION_CTRL_EVT_RESET_REPLY);
   rmp = (session_reset_reply_msg_t *) app_evt->evt->data;
   rmp->retval = rv;
   rmp->handle = mp->handle;
-  app_send_ctrl_evt_to_vpp (session->vpp_evt_q, app_evt);
+  app_send_ctrl_evt_to_vpp (s->vpp_evt_q, app_evt);
 }
 
 static void
@@ -1552,47 +1244,68 @@ static int
 wait_for_state_change (echo_main_t * em, connection_state_t state,
 		       f64 timeout)
 {
-  svm_msg_q_msg_t msg;
-  session_event_t *e;
   f64 end_time = clib_time_now (&em->clib_time) + timeout;
-
   while (!timeout || clib_time_now (&em->clib_time) < end_time)
     {
       if (em->state == state)
 	return 0;
-      if (em->time_to_stop == 1)
-	return 0;
-      if (!em->our_event_queue || em->state < STATE_ATTACHED)
-	continue;
-
-      if (svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_NOWAIT, 0))
-	continue;
-      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
-      handle_mq_event (e);
-      svm_msg_q_free_msg (em->our_event_queue, &msg);
+      if (em->time_to_stop)
+	return 1;
     }
   ECHO_LOG (1, "timeout waiting for %U", format_quic_echo_state, state);
   return -1;
 }
 
 static void
-echo_event_loop (echo_main_t * em)
+echo_process_rpcs (echo_main_t * em)
 {
+  echo_rpc_msg_t *rpc;
   svm_msg_q_msg_t msg;
+  while (em->state < STATE_DATA_DONE && !em->time_to_stop)
+    {
+      if (svm_msg_q_sub (em->rpc_msq_queue, &msg, SVM_Q_TIMEDWAIT, 1))
+	continue;
+      rpc = svm_msg_q_msg_data (em->rpc_msq_queue, &msg);
+      ((echo_rpc_t) rpc->fp) (rpc->arg, rpc->opaque);
+      svm_msg_q_free_msg (em->rpc_msq_queue, &msg);
+    }
+}
+
+static void *
+echo_mq_thread_fn (void *arg)
+{
+  clib_mem_set_thread_index ();
+  echo_main_t *em = &echo_main;
   session_event_t *e;
+  svm_msg_q_msg_t msg;
+  int rv;
+  wait_for_state_change (em, STATE_ATTACHED, 0);
+  if (em->state < STATE_ATTACHED || !em->our_event_queue)
+    {
+      ECHO_FAIL ("Application failed to attach");
+      pthread_exit (0);
+    }
 
   ECHO_LOG (1, "Waiting for data on %u clients", em->n_clients_connected);
-  while (em->n_clients_connected | em->n_quic_clients_connected)
+  while (1)
     {
-      int rc = svm_msg_q_sub (em->our_event_queue, &msg, SVM_Q_TIMEDWAIT, 1);
-      if (PREDICT_FALSE (rc == ETIMEDOUT && em->time_to_stop))
+      if (!(rv = svm_msg_q_sub (em->our_event_queue,
+				&msg, SVM_Q_TIMEDWAIT, 1)))
+	{
+	  e = svm_msg_q_msg_data (em->our_event_queue, &msg);
+	  handle_mq_event (e);
+	  svm_msg_q_free_msg (em->our_event_queue, &msg);
+	}
+      if (rv == ETIMEDOUT
+	  && (em->time_to_stop || em->state == STATE_DETACHED))
 	break;
-      if (rc == ETIMEDOUT)
-	continue;
-      e = svm_msg_q_msg_data (em->our_event_queue, &msg);
-      handle_mq_event (e);
-      svm_msg_q_free_msg (em->our_event_queue, &msg);
+      if (!em->n_clients_connected && !em->n_quic_clients_connected &&
+	  em->state == STATE_READY)
+	{
+	  em->state = STATE_DATA_DONE;
+	}
     }
+  pthread_exit (0);
 }
 
 static void
@@ -1601,28 +1314,19 @@ clients_run (echo_main_t * em)
   u64 i;
   quic_echo_notify_event (em, ECHO_EVT_FIRST_QCONNECT);
   for (i = 0; i < em->n_clients; i++)
-    echo_send_connect (em, em->uri, SESSION_INVALID_INDEX);
-
-  if (wait_for_state_change (em, STATE_READY, TIMEOUT))
-    {
-      ECHO_FAIL ("Timeout waiting for state ready");
-      return;
-    }
-
-  echo_event_loop (em);
+    echo_send_connect (em->uri, SESSION_INVALID_INDEX);
+  wait_for_state_change (em, STATE_READY, 0);
+  ECHO_LOG (1, "App is ready");
+  echo_process_rpcs (em);
 }
 
 static void
 server_run (echo_main_t * em)
 {
   server_send_listen (em);
-  if (wait_for_state_change (em, STATE_READY, 0))
-    {
-      ECHO_FAIL ("Timeout waiting for state ready");
-      return;
-    }
-  echo_event_loop (em);
-
+  wait_for_state_change (em, STATE_READY, 0);
+  ECHO_LOG (1, "App is ready");
+  echo_process_rpcs (em);
   /* Cleanup */
   server_send_unbind (em);
   if (wait_for_state_change (em, STATE_DISCONNECTED, TIMEOUT))
@@ -1638,7 +1342,6 @@ server_run (echo_main_t * em)
  *
  */
 
-
 static void
 vl_api_application_attach_reply_t_handler (vl_api_application_attach_reply_t *
 					   mp)
@@ -1706,9 +1409,7 @@ vl_api_application_attach_reply_t_handler (vl_api_application_attach_reply_t *
 	  return;
 	}
     }
-  clib_spinlock_lock (&em->segment_handles_lock);
-  hash_set (em->shared_segment_handles, segment_handle, 1);
-  clib_spinlock_unlock (&em->segment_handles_lock);
+  echo_segment_handle_add_del (em, segment_handle, 1 /* add */ );
   ECHO_LOG (1, "Mapped segment 0x%lx", segment_handle);
 
   em->state = STATE_ATTACHED;
@@ -1737,10 +1438,7 @@ vl_api_unmap_segment_t_handler (vl_api_unmap_segment_t * mp)
 {
   echo_main_t *em = &echo_main;
   u64 segment_handle = clib_net_to_host_u64 (mp->segment_handle);
-
-  clib_spinlock_lock (&em->segment_handles_lock);
-  hash_unset (em->shared_segment_handles, segment_handle);
-  clib_spinlock_unlock (&em->segment_handles_lock);
+  echo_segment_handle_add_del (em, segment_handle, 0 /* add */ );
   ECHO_LOG (1, "Unmaped segment 0x%lx", segment_handle);
 }
 
@@ -1783,9 +1481,7 @@ vl_api_map_another_segment_t_handler (vl_api_map_another_segment_t * mp)
 	  goto failed;
 	}
     }
-  clib_spinlock_lock (&em->segment_handles_lock);
-  hash_set (em->shared_segment_handles, segment_handle, 1);
-  clib_spinlock_unlock (&em->segment_handles_lock);
+  echo_segment_handle_add_del (em, segment_handle, 1 /* add */ );
   ECHO_LOG (1, "Mapped segment 0x%lx", segment_handle);
   return;
 
@@ -1821,7 +1517,7 @@ vl_api_unbind_uri_reply_t_handler (vl_api_unbind_uri_reply_t * mp)
     }
   em->state = STATE_DISCONNECTED;
   listen_session = pool_elt_at_index (em->sessions, em->listen_session_index);
-  echo_initiate_session_close (em, listen_session, 1 /* active */ );
+  echo_cleanup_session (em, listen_session);
 }
 
 static void
@@ -1830,7 +1526,6 @@ vl_api_disconnect_session_reply_t_handler (vl_api_disconnect_session_reply_t *
 {
   echo_main_t *em = &echo_main;
   echo_session_t *s;
-  uword *p;
 
   if (mp->retval)
     {
@@ -1839,15 +1534,12 @@ vl_api_disconnect_session_reply_t_handler (vl_api_disconnect_session_reply_t *
     }
 
   ECHO_LOG (1, "Got disonnected reply for session 0x%lx", mp->handle);
-  p = hash_get (em->session_index_by_vpp_handles, mp->handle);
-  if (!p)
-    {
-      ECHO_FAIL ("couldn't find session key %llx", mp->handle);
-      return;
-    }
-
-  s = pool_elt_at_index (em->sessions, p[0]);
-  echo_initiate_session_close (em, s, 1 /* active */ );
+  if (!(s = echo_get_session_from_handle (em, mp->handle)))
+    return;
+  if (s->session_type == QUIC_SESSION_TYPE_STREAM)
+    s->session_state = QUIC_SESSION_STATE_CLOSING;
+  else
+    echo_cleanup_session (em, s);	/* We can clean Q/Lsessions right away */
 }
 
 static void
@@ -1878,15 +1570,17 @@ vl_api_connect_uri_reply_t_handler (vl_api_connect_uri_reply_t * mp)
   if (mp->context == SESSION_INVALID_INDEX)
     {
       ECHO_LOG (1, "Retrying connect %s", em->uri);
-      echo_send_connect (em, em->uri, SESSION_INVALID_INDEX);
+      echo_send_rpc (em, echo_send_connect, (void *) em->uri,
+		     SESSION_INVALID_INDEX);
     }
   else
     {
       session = pool_elt_at_index (em->sessions, mp->context);
       uri = format (0, "QUIC://session/%lu", session->vpp_session_handle);
       ECHO_LOG (1, "Retrying connect %s", uri);
-      echo_send_connect (em, uri, mp->context);
+      echo_send_rpc (em, echo_send_connect, (void *) uri, mp->context);
     }
+
 }
 
 #define foreach_quic_echo_msg                            		\
@@ -1957,6 +1651,7 @@ print_usage_and_exit (void)
 	   "                       exit        - Exiting of the app\n"
 	   "  json                Output global stats in json\n"
 	   "  log=N               Set the log level to [0: no output, 1:errors, 2:log]\n"
+	   "  max-connects=N      Don't do more than N parallel connect_uri\n"
 	   "\n"
 	   "  nclients N[/M]      Open N QUIC connections, each one with M streams (M defaults to 1)\n"
 	   "  nthreads N          Use N busy loop threads for data [in addition to main & msg queue]\n"
@@ -2047,8 +1742,8 @@ quic_echo_process_opts (int argc, char **argv)
 	    (a, "qclose=%U", unformat_close, &em->send_quic_disconnects))
 	;
       else if (unformat (a, "time %U:%U",
-			 echo_unformat_timing_event, &em->timing_start_event,
-			 echo_unformat_timing_event, &em->timing_end_event))
+			 echo_unformat_timing_event, &em->timing.start_event,
+			 echo_unformat_timing_event, &em->timing.end_event))
 	;
       else
 	print_usage_and_exit ();
@@ -2091,13 +1786,16 @@ main (int argc, char **argv)
   echo_main_t *em = &echo_main;
   fifo_segment_main_t *sm = &em->segment_main;
   char *app_name;
-  u32 n_clients, i;
+  u64 n_clients, i;
+  svm_msg_q_cfg_t _cfg, *cfg = &_cfg;
+  u32 rpc_queue_size = 64 << 10;
 
   clib_mem_init_thread_safe (0, 256 << 20);
   clib_memset (em, 0, sizeof (*em));
   em->session_index_by_vpp_handles = hash_create (0, sizeof (uword));
+  clib_spinlock_init (&em->sid_vpp_handles_lock);
   em->shared_segment_handles = hash_create (0, sizeof (uword));
-  em->my_pid = getpid ();
+  clib_spinlock_init (&em->segment_handles_lock);
   em->socket_name = format (0, "%s%c", API_SOCKET_FILE, 0);
   em->use_sock_api = 1;
   em->fifo_size = 64 << 10;
@@ -2108,8 +1806,8 @@ main (int argc, char **argv)
   em->i_am_master = 1;
   em->n_rx_threads = 4;
   em->test_return_packets = RETURN_PACKETS_NOTEST;
-  em->timing_start_event = ECHO_EVT_FIRST_QCONNECT;
-  em->timing_end_event = ECHO_EVT_LAST_BYTE;
+  em->timing.start_event = ECHO_EVT_FIRST_QCONNECT;
+  em->timing.end_event = ECHO_EVT_LAST_BYTE;
   em->bytes_to_receive = ~0;	/* defaulted when we know if server/client */
   em->bytes_to_send = ~0;	/* defaulted when we know if server/client */
   em->rx_buf_size = 1 << 20;
@@ -2120,35 +1818,63 @@ main (int argc, char **argv)
   quic_echo_process_opts (argc, argv);
 
   n_clients = em->n_clients * em->n_stream_clients;
-  vec_validate (em->client_thread_handles, em->n_rx_threads - 1);
-  vec_validate (em->thread_args, n_clients - 1);
+  vec_validate (em->data_thread_handles, em->n_rx_threads - 1);
+  vec_validate (em->data_thread_args, n_clients - 1);
+  for (i = 0; i < n_clients; i++)
+    em->data_thread_args[i] = SESSION_INVALID_INDEX;
   clib_time_init (&em->clib_time);
-  init_error_string_table (em);
+  init_error_string_table ();
   fifo_segment_main_init (sm, HIGH_SEGMENT_BASEVA, 20);
-  clib_spinlock_init (&em->segment_handles_lock);
   vec_validate (em->connect_test_data, em->tx_buf_size);
   for (i = 0; i < em->tx_buf_size; i++)
     em->connect_test_data[i] = i & 0xff;
 
-  setup_signal_handlers ();
+  /* *INDENT-OFF* */
+  svm_msg_q_ring_cfg_t rc[SESSION_MQ_N_RINGS] = {
+    {rpc_queue_size, sizeof (echo_rpc_msg_t), 0},
+  };
+  /* *INDENT-ON* */
+  cfg->consumer_pid = getpid ();
+  cfg->n_rings = 1;
+  cfg->q_nitems = rpc_queue_size;
+  cfg->ring_cfgs = rc;
+  em->rpc_msq_queue = svm_msg_q_alloc (cfg);
+
+  signal (SIGINT, stop_signal);
+  signal (SIGQUIT, stop_signal);
+  signal (SIGTERM, stop_signal);
   quic_echo_api_hookup (em);
 
   app_name = em->i_am_master ? "quic_echo_server" : "quic_echo_client";
   if (connect_to_vpp (app_name) < 0)
     {
       svm_region_exit ();
-      ECHO_FAIL ("ECHO-ERROR: Couldn't connect to vpe, exiting...\n");
+      ECHO_FAIL ("Couldn't connect to vpe, exiting...\n");
       exit (1);
     }
 
+  echo_session_prealloc (em);
   quic_echo_notify_event (em, ECHO_EVT_START);
 
   application_send_attach (em);
   if (wait_for_state_change (em, STATE_ATTACHED, TIMEOUT))
     {
-      ECHO_FAIL ("ECHO-ERROR: Couldn't attach to vpp, exiting...\n");
+      ECHO_FAIL ("Couldn't attach to vpp, did you run <session enable> ?\n");
+      exit (1);
+    }
+  if (pthread_create (&em->mq_thread_handle,
+		      NULL /*attr */ , echo_mq_thread_fn, 0))
+    {
+      ECHO_FAIL ("pthread create errored\n");
       exit (1);
     }
+  for (i = 0; i < em->n_rx_threads; i++)
+    if (pthread_create (&em->data_thread_handles[i],
+			NULL /*attr */ , echo_data_thread_fn, (void *) i))
+      {
+	ECHO_FAIL ("pthread create errored\n");
+	exit (1);
+      }
   if (em->i_am_master)
     server_run (em);
   else
@@ -2166,6 +1892,13 @@ main (int argc, char **argv)
       ECHO_FAIL ("ECHO-ERROR: Couldn't detach from vpp, exiting...\n");
       exit (1);
     }
+  int *rv;
+  pthread_join (em->mq_thread_handle, (void **) &rv);
+  if (rv)
+    {
+      ECHO_FAIL ("mq pthread errored %d", rv);
+      exit (1);
+    }
   if (em->use_sock_api)
     vl_socket_client_disconnect ();
   else
diff --git a/src/plugins/hs_apps/sapi/quic_echo.h b/src/plugins/hs_apps/sapi/quic_echo.h
new file mode 100644
index 00000000000..aec56d077f0
--- /dev/null
+++ b/src/plugins/hs_apps/sapi/quic_echo.h
@@ -0,0 +1,246 @@
+/*
+ * Copyright (c) 2019 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <signal.h>
+
+#include <vnet/session/application_interface.h>
+
+#define vl_typedefs		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_typedefs
+
+/* declare message handlers for each api */
+
+#define vl_endianfun		/* define message structures */
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...)
+#define vl_printfun
+#include <vpp/api/vpe_all_api_h.h>
+#undef vl_printfun
+
+#define NITER 4000000
+#define TIMEOUT 10.0
+
+#define CHECK(expected, result, _fmt, _args...)		\
+    if (expected != result)				\
+      ECHO_FAIL ("expected %d, got %d : " _fmt, expected, result, ##_args);
+
+#define ECHO_FAIL(_fmt,_args...)	\
+  {					\
+    echo_main_t *em = &echo_main;	\
+    em->has_failed = 1;		\
+    em->time_to_stop = 1;		\
+    if (em->log_lvl > 0)		\
+      clib_warning ("ECHO-ERROR: "_fmt, ##_args); 	\
+  }
+
+#define ECHO_LOG(lvl, _fmt,_args...)	\
+  {					\
+    echo_main_t *em = &echo_main;	\
+    if (em->log_lvl > lvl)		\
+      clib_warning (_fmt, ##_args); 	\
+  }
+
+typedef struct
+{
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+#define _(type, name) type name;
+  foreach_app_session_field
+#undef _
+  u64 vpp_session_handle;
+  u64 bytes_sent;
+  u64 bytes_to_send;
+  volatile u64 bytes_received;
+  volatile u64 bytes_to_receive;
+  f64 start;
+  u32 listener_index;		/* listener index in echo session pool */
+  u32 idle_cycles;		/* consecutive enq/deq with no data */
+  volatile u64 accepted_session_count;	/* sessions we accepted */
+} echo_session_t;
+
+typedef enum
+{
+  ECHO_NO_DATA_SOURCE,
+  ECHO_TEST_DATA_SOURCE,
+  ECHO_RX_DATA_SOURCE,
+  ECHO_INVALID_DATA_SOURCE
+} data_source_t;
+
+enum echo_close_f_t
+{
+  ECHO_CLOSE_F_INVALID = 0,
+  ECHO_CLOSE_F_PASSIVE,		/* wait for close msg */
+  ECHO_CLOSE_F_ACTIVE,		/* send close msg */
+  ECHO_CLOSE_F_NONE,		/* don't bother sending close msg */
+};
+
+enum quic_session_type_t
+{
+  QUIC_SESSION_TYPE_QUIC,
+  QUIC_SESSION_TYPE_STREAM,
+  QUIC_SESSION_TYPE_LISTEN,
+};
+
+enum quic_session_state_t
+{
+  QUIC_SESSION_STATE_INITIAL,
+  QUIC_SESSION_STATE_READY,
+  QUIC_SESSION_STATE_AWAIT_CLOSING,	/* Data transfer is done, wait for close evt */
+  QUIC_SESSION_STATE_AWAIT_DATA,	/* Peer closed, wait for outstanding data */
+  QUIC_SESSION_STATE_CLOSING,	/* told vpp to close */
+  QUIC_SESSION_STATE_CLOSED,	/* closed in vpp */
+};
+
+typedef enum
+{
+  STATE_START,
+  STATE_ATTACHED,
+  STATE_LISTEN,
+  STATE_READY,
+  STATE_DATA_DONE,
+  STATE_DISCONNECTED,
+  STATE_DETACHED
+} connection_state_t;
+
+typedef enum echo_test_evt_
+{
+  ECHO_EVT_START = 1,		/* app starts */
+  ECHO_EVT_FIRST_QCONNECT = (1 << 1),	/* First connect Quic session sent */
+  ECHO_EVT_LAST_QCONNECTED = (1 << 2),	/* All Quic session are connected */
+  ECHO_EVT_FIRST_SCONNECT = (1 << 3),	/* First connect Stream session sent */
+  ECHO_EVT_LAST_SCONNECTED = (1 << 4),	/* All Stream session are connected */
+  ECHO_EVT_LAST_BYTE = (1 << 5),	/* Last byte received */
+  ECHO_EVT_EXIT = (1 << 6),	/* app exits */
+} echo_test_evt_t;
+
+typedef struct _quic_echo_cb_vft
+{
+  void (*quic_connected_cb) (session_connected_msg_t * mp, u32 session_index);
+  void (*client_stream_connected_cb) (session_connected_msg_t * mp,
+				      u32 session_index);
+  void (*server_stream_connected_cb) (session_connected_msg_t * mp,
+				      u32 session_index);
+  void (*quic_accepted_cb) (session_accepted_msg_t * mp, u32 session_index);
+  void (*client_stream_accepted_cb) (session_accepted_msg_t * mp,
+				     u32 session_index);
+  void (*server_stream_accepted_cb) (session_accepted_msg_t * mp,
+				     u32 session_index);
+} quic_echo_cb_vft_t;
+
+
+typedef enum
+{
+  RETURN_PACKETS_NOTEST,
+  RETURN_PACKETS_LOG_WRONG,
+  RETURN_PACKETS_ASSERT,
+} test_return_packets_t;
+
+typedef struct teardown_stat_
+{
+  u32 q; /* quic sessions */
+  u32 s; /* stream sessions */
+} teardown_stat_t;
+
+typedef struct
+{
+  svm_queue_t *vl_input_queue;	/* vpe input queue */
+  u32 my_client_index;		/* API client handle */
+  u8 *uri;			/* The URI we're playing with */
+  echo_session_t *sessions;	/* Session pool */
+  svm_msg_q_t *our_event_queue;	/* Our event queue */
+  clib_time_t clib_time;	/* For deadman timers */
+  u8 *socket_name;
+  int i_am_master;
+  u32 listen_session_index;	/* Index of vpp listener session */
+
+  uword *session_index_by_vpp_handles;	/* Hash table : quic_echo s_id -> vpp s_handle */
+  clib_spinlock_t sid_vpp_handles_lock;	/* Hash table lock */
+
+  uword *shared_segment_handles;	/* Hash table : segment_names -> 1*/
+  clib_spinlock_t segment_handles_lock;	/* Hash table lock */
+  quic_echo_cb_vft_t cb_vft;	/* cb vft for QUIC scenarios */
+  svm_msg_q_t *rpc_msq_queue;	/* MQ between quic_echo threads */
+  fifo_segment_main_t segment_main;
+
+  /* State of the connection, shared between msg RX thread and main thread */
+  volatile connection_state_t state;
+  volatile u8 time_to_stop;	/* Signal variables */
+  u8 has_failed;		/* stores the exit code */
+
+  /** Flag that decides if socket, instead of svm, api is used to connect to
+   * vpp. If sock api is used, shm binary api is subsequently bootstrapped
+   * and all other messages are exchanged using shm IPC. */
+  u8 use_sock_api;
+
+  u8 *connect_test_data;
+  u8 test_return_packets;
+  u64 bytes_to_send;		/* target per stream */
+  u64 bytes_to_receive;		/* target per stream */
+  u32 fifo_size;
+  u32 rx_buf_size;
+  u32 tx_buf_size;
+  data_source_t data_source;	/* Use no/dummy/mirrored data */
+  u8 send_quic_disconnects;	/* actively send disconnect */
+  u8 send_stream_disconnects;	/* actively send disconnect */
+  u8 output_json;		/* Output stats as JSON */
+  u8 log_lvl;			/* Verbosity of the logging */
+  int max_test_msg;		/* Limit the number of incorrect data messages */
+
+  u8 *appns_id;
+  u64 appns_flags;
+  u64 appns_secret;
+
+  pthread_t *data_thread_handles;	/* vec of data thread handles */
+  pthread_t mq_thread_handle;	/* Message queue thread handle */
+  u32 *data_thread_args;
+
+  u32 n_clients;		/* Target number of QUIC sessions */
+  u32 n_stream_clients;		/* Target Number of STREAM sessions per QUIC session */
+  volatile u32 n_quic_clients_connected;	/* Number of connected QUIC sessions */
+  volatile u32 n_clients_connected;	/* Number of STREAM sessions connected */
+  u32 n_rx_threads;		/* Number of data threads */
+  volatile u32 nxt_available_sidx; /* next unused prealloced session_index */
+
+  struct {
+    u64 tx_total;
+    u64 rx_total;
+    teardown_stat_t reset_count; /* received reset from vpp */
+    teardown_stat_t close_count; /* received close from vpp */
+    teardown_stat_t active_count; /* sent close to vpp */
+    teardown_stat_t clean_count; /* cleaned up stale session */
+  } stats;
+
+  struct /* Event based timing : start & end depend on CLI specified events */
+  {
+    f64 start_time;
+    f64 end_time;
+    u8 events_sent;
+    u8 start_event;
+    u8 end_event;
+  } timing;
+} echo_main_t;
+
+typedef void (*echo_rpc_t) (void *arg, u32 opaque);
+
+typedef struct
+{
+  void *fp;
+  void *arg;
+  u32 opaque;
+} echo_rpc_msg_t;