Add new net stats for streams and requests (#2887)

Fixes #2420 #2413 

Co-authored-by: Patience Daur <[email protected]>

Author: p7nov

doc/reference/reference_lua/box_stat/net.rst

@@ -6,7 +6,7 @@ box.stat.net()
 .. function:: net()
 
     Shows network activity: the number of bytes sent
-    and received, the number of connections, and the number of active requests
+    and received, the number of connections, streams, and requests
     (current, average, and total).
 
     :return: in the tables that ``box.stat.net()`` returns:
@@ -15,27 +15,50 @@ box.stat.net()
           second in the last 5 seconds
         * ``SENT.total`` and ``RECEIVED.total`` -- total number of bytes sent/received
           since the server started
-        * ``CONNECTIONS.rps`` -- number of connections opened per second in the last 5 seconds
+        * ``CONNECTIONS.current`` -- number of open connections
+        * ``CONNECTIONS.rps`` -- average number of connections opened per second in the last 5 seconds
         * ``CONNECTIONS.total`` -- total number of connections opened since the server started
         * ``REQUESTS.current`` -- number of requests in progress, which can be
           limited by :ref:`box.cfg.net_msg_max <cfg_networking-net_msg_max>`
-        * ``REQUESTS.rps`` -- number of requests processed per second in the last 5 seconds
-        * ``REQUESTS.total`` -- total number of requests processed since startup
+        * ``REQUESTS.rps`` -- average number of requests processed per second in the last 5 seconds
+        * ``REQUESTS.total`` -- total number of requests processed since the server started
+        * ``REQUESTS_IN_PROGRESS.current`` -- number of requests being currently processed by the :ref:`TX thread <memtx-memory>`
+        * ``REQUESTS_IN_PROGRESS.rps`` -- average number of requests processed by the TX thread per second in the last 5 seconds
+        * ``REQUESTS_IN_PROGRESS.total`` -- total number of requests processed by the TX thread since the server started
+        * ``STREAMS.current`` -- number of active :doc:`streams </book/box/stream>`
+        * ``STREAMS.rps`` -- average number of streams opened per second in the last 5 seconds
+        * ``STREAMS.total`` -- total number of streams opened since the server started
+        * ``REQUESTS_IN_STREAM_QUEUE.current`` -- number of requests waiting in stream queues
+        * ``REQUESTS_IN_STREAM_QUEUE.rps`` -- average number of requests in stream queues per second in the last 5 seconds
+        * ``REQUESTS_IN_STREAM_QUEUE.total`` -- total number of requests placed in stream queues since the server started
+
 
     **Example:**
 
     .. code-block:: tarantoolsession
 
-        tarantool> box.stat.net() -- 4 tables
+        tarantool> box.stat.net() -- 5 tables
         ---
-        - SENT:
+        - CONNECTIONS:
+            current: 0
+            rps: 0
+            total: 0
+          REQUESTS:
+            current: 0
+            rps: 0
+            total: 0
+          REQUESTS_IN_PROGRESS:
+            current: 0
+            rps: 0
+            total: 0
+          SENT:
             total: 0
             rps: 0
-          CONNECTIONS:
+          REQUESTS_IN_STREAM_QUEUE:
             current: 0
             rps: 0
             total: 0
-          REQUESTS:
+          STREAMS:
             current: 0
             rps: 0
             total: 0