Clean-up config options

src/mtp_dc_pool.erl

@@ -33,7 +33,8 @@
 -define(SERVER, ?MODULE).
 -define(APP, mtproto_proxy).
 -define(BURST_MAX, 10).
--define(DEFAULT_INIT_CONNS, 4).
+-define(DEFAULT_INIT_CONNS, 2).
+-define(DEFAULT_CLIENTS_PER_CONN, 300).
 
 -type upstream() :: mtp_handler:handle().
 -type downstream() :: mtp_down_conn:handle().
@@ -224,12 +225,12 @@ maybe_spawn_connection(CurrentMin, #state{pending_downstreams = Pending} = St) -
     %% if N > X and len(pending) < Y -> connect()
     %% TODO: shrinking (by timer)
     ToSpawn =
-        case application:get_env(?APP, clients_per_dc_connection) of
-            {ok, N} when CurrentMin > N,
-                         Pending == [] ->
+        case application:get_env(?APP, clients_per_dc_connection, ?DEFAULT_CLIENTS_PER_CONN) of
+            N when CurrentMin > N,
+                   Pending == [] ->
                 2;
-            {ok, N} when CurrentMin > (N * 1.5),
-                         length(Pending) < ?BURST_MAX ->
+            N when CurrentMin > (N * 1.5),
+                   length(Pending) < ?BURST_MAX ->
                 %% To survive initial bursts
                 ?BURST_MAX - length(Pending);
             _ ->

src/mtp_down_conn.erl

@@ -36,6 +36,7 @@
 -define(HANDSHAKE_TIMEOUT, 8000).
 -define(MAX_SOCK_BUF_SIZE, 1024 * 500).    % Decrease if CPU is cheaper than RAM
 -define(MAX_CODEC_BUFFERS, 5 * 1024 * 1024).
+-define(DEFAULT_CLIENTS_PER_CONN, 300).
 
 -ifndef(OTP_RELEASE).                           % pre-OTP21
 -define(WITH_STACKTRACE(T, R, S), T:R -> S = erlang:get_stacktrace(), ).
@@ -110,7 +111,7 @@ set_config(Conn, Option, Value) ->
 init([Pool, DcId]) ->
     self() ! do_connect,
     BpOpts = application:get_env(?APP, downstream_backpressure, #{}),
-    {ok, UpsPerDown} = application:get_env(?APP, clients_per_dc_connection),
+    UpsPerDown = application:get_env(?APP, clients_per_dc_connection, ?DEFAULT_CLIENTS_PER_CONN),
     BackpressureConf = build_backpressure_conf(UpsPerDown, BpOpts),
     {ok, #state{backpressure_conf = BackpressureConf,
                 pool = Pool,
@@ -128,7 +129,7 @@ handle_call({set_config, Name, Value}, _From, State) ->
                 ok = inet:setopts(State#state.sock, [{buffer, Value}]),
                 {{ok, OldSize}, State};
             downstream_backpressure when is_map(Value) ->
-                {ok, UpsPerDown} = application:get_env(?APP, clients_per_dc_connection),
+                UpsPerDown = application:get_env(?APP, clients_per_dc_connection, ?DEFAULT_CLIENTS_PER_CONN),
                 try build_backpressure_conf(UpsPerDown, Value) of
                     BpConfig ->
                         {{ok, State#state.backpressure_conf},

src/mtproto_proxy.app.src

@@ -14,35 +14,13 @@
     stdlib
    ]},
   {env,[
-        %% Close connection if it failed to perform handshake in this many seconds
-        {init_timeout_sec, 60},
-        {hibernate_timeout_sec, 60},
-        %% Close connection after this many seconds of inactivity
-        {ready_timeout_sec, 1200},
-
-        %% Telegram server uses your external IP address as part of encryption
-        %% key, so, you should know it.
-        %% You can configure IP lookup services by `ip_lookup_services' (should
-        %% return my IP address as one line from this URL) or set IP address
-        %% statically by `external_ip' (not both).
-        %% If both are unset, proxy will try to guess IP address
-        %% from getsockname().
-        %% `ip_lookup_services' will be tried one-by-one: if 1st is not responding,
-        %% 2nd one will be tried and so on
-        {ip_lookup_services,
-         ["http://ipv4.seriyps.ru/",
-          "http://v4.ident.me/",
-          "http://ipv4.icanhazip.com/",
-          "https://digitalresistance.dog/myIp"]},
-        %% {external_ip, "YOUR.SERVER.EXTERNAL.IP"},
-
         %% Interface to listen for incoming connections
-        %% If not set, 0.0.0.0 will be used
+        %% If not set, 0.0.0.0 will be used (listen on all IPs)
         {listen_ip, "0.0.0.0"},
         %% You can add as much as you want. Names and ports should be unique
         {ports, [#{name => mtp_handler_1,
                    port => 1443,
-                   %% You can tell it to listen on specific IP.
+                   %% You can tell each port to listen on specific IP.
                    %% If not set, top-level listen_ip will be used.
                    %% listen_ip => "1.2.3.4",
 
@@ -50,8 +28,12 @@
                    secret => <<"d0d6e111bada5511fcce9584deadbeef">>,
                    %% tag is what you get from @MTProxybot
                    tag => <<"dcbe8f1493fa4cd9ab300891c0b5b326">>}]},
+
+        %% number of socket acceptors (per-port)
         {num_acceptors, 60},
-        {max_connections, 40960},
+        %% maximum number of open connections (per-port)
+        {max_connections, 64000},
+
         %% It's possible to forbid connection from telegram client to proxy
         %% with some of the protocols. Ti's recommended to set this to
         %% only `{allowed_protocols, [mtp_secure, mtp_fake_tls]}` because those
@@ -67,8 +49,28 @@
         %%   {max_connections, [port_name, tls_domain], 15}
         %%  ]},
 
-        {init_dc_connections, 2},
-        {clients_per_dc_connection, 300},
+        %% Close connection if it failed to perform handshake in this many seconds
+        {init_timeout_sec, 60},
+        %% Switch client to memory-saving mode after this many seconds of inactivity
+        {hibernate_timeout_sec, 60},
+        %% Close client connection after this many seconds of inactivity
+        {ready_timeout_sec, 1200},
+
+        %% Telegram server uses your external IP address as part of encryption
+        %% key, so, you should know it.
+        %% You can configure IP lookup services by `ip_lookup_services' (should
+        %% return my IP address as one line from this URL) or set IP address
+        %% statically by `external_ip' (not both).
+        %% If both are unset, proxy will try to guess IP address
+        %% from getsockname().
+        %% `ip_lookup_services' will be tried one-by-one: if 1st is not responding,
+        %% 2nd one will be tried and so on
+        {ip_lookup_services,
+         ["http://ipv4.seriyps.ru/",
+          "http://v4.ident.me/",
+          "http://ipv4.icanhazip.com/",
+          "https://digitalresistance.dog/myIp"]},
+        %% {external_ip, "YOUR.SERVER.EXTERNAL.IP"},
 
         %% This option controls how proxy closes client sockets
         %% (SO_LINGER timeout=0 socket option)
@@ -85,6 +87,9 @@
         %% - always - always close socket with RST
         {reset_close_socket, off},
 
+        %% List of enabled replay-attack checks. See
+        %% https://habr.com/ru/post/452144/
+
         %% server_error_filter - drop server error responses.
         %% Values:
         %%     first - drop server error only if it's 1st server packet
@@ -93,10 +98,8 @@
         %% Default: off
         {replay_check_server_error_filter, first},
 
-        %% List of enabled replay-attack checks. See
-        %% https://habr.com/ru/post/452144/
-        %% session_storage - store last used 1st client packets in special
-        %% storage, drop connections with same 1st packet
+        %% Store last used 1st client packets in special storage, drop
+        %% connections with same 1st packet
         %% Values: on/off
         %% Default: off
         {replay_check_session_storage, on},
@@ -139,6 +142,10 @@
         %%   {total_mem, 3145728} % if connection memory >X - close connection
         %%  ]},
 
+        %% Multiplexing tuning
+        %% {init_dc_connections, 2},
+        %% {clients_per_dc_connection, 300},
+
         %% Downstream backpressure tuning
         %% Values are configured per downstream connection, so, for example, if
         %% `clients_per_dc_connection' is 300 and current number of connections