Cuttlefish schema: introduce socket_writer.gc_threshold

References rabbitmq#2182, rabbitmq/rabbitmq-common#343.

docs/rabbitmq.conf.example

@@ -40,6 +40,13 @@
 # num_acceptors.tcp = 10
 # num_acceptors.ssl = 10
 
+## Socket writer will force GC every so many bytes transferred.
+## Default is 1 GiB (`1000000000`). Set to 'off' to disable.
+##
+# socket_writer.gc_threshold = 1000000000
+#
+## To disable:
+# socket_writer.gc_threshold = off
 
 ## Maximum amount of time allowed for the AMQP 0-9-1 and AMQP 1.0 handshake
 ## (performed after socket connection and TLS handshake) to complete, in milliseconds.

priv/schema/rabbit.schema

@@ -59,7 +59,7 @@ fun(Conf) ->
 end}.
 
 %% Number of Erlang processes that will accept connections for the TCP
-%% and SSL listeners.
+%% and TLS listeners.
 %%
 %% {num_tcp_acceptors, 10},
 %% {num_ssl_acceptors, 1},
@@ -73,13 +73,32 @@ end}.
 ]}.
 
 
+{mapping, "socket_writer.gc_threshold", "rabbit.writer_gc_threshold", [
+    {datatype, [{atom, off}, integer]}
+]}.
+
+{translation, "rabbit.writer_gc_threshold",
+    fun(Conf) ->
+            case cuttlefish:conf_get("socket_writer.gc_threshold", Conf, undefined) of
+                %% missing from the config
+                undefined -> cuttlefish:unset();
+                %% explicitly disabled
+                off -> undefined;
+                Int when is_integer(Int) andalso Int > 0 ->
+                    Int;
+                _ ->
+                    cuttlefish:invalid("should be a non-negative integer")
+            end
+    end
+}.
+
 %% Maximum time for 0-9-1 handshake (after socket connection
-%% and SSL handshake), in milliseconds.
+%% and TLS handshake), in milliseconds.
 %%
 %% {handshake_timeout, 10000},
 
 {mapping, "handshake_timeout", "rabbit.handshake_timeout", [
-    {datatype, integer}
+    {datatype, [{atom, infinity}, integer]}
 ]}.
 
 %% Set to 'true' to perform reverse DNS lookups when accepting a

test/config_schema_SUITE_data/rabbit.snippets

@@ -71,6 +71,13 @@ ssl_options.fail_if_no_peer_cert = true",
   "listeners.ssl = none",[{rabbit,[{ssl_listeners,[]}]}],[]},
  {num_acceptors,
   "num_acceptors.ssl = 1",[{rabbit,[{num_ssl_acceptors,1}]}],[]},
+
+ {socket_writer_gc_threshold,
+  "socket_writer.gc_threshold = 999666111", [{rabbit, [{writer_gc_threshold, 999666111}]}],[]},
+
+ {socket_writer_gc_threshold_off,
+  "socket_writer.gc_threshold = off", [{rabbit, [{writer_gc_threshold, undefined}]}],[]},
+
  {default_user_settings,
   "default_user = guest
 default_pass = guest