Rozmiar wiadomości maksymalna w RabbitMQ było 2 GiB przed wersją 3.8.0:
%% Trying to send a term across a cluster larger than 2^31 bytes will
%% cause the VM to exit with "Absurdly large distribution output data
%% buffer". So we limit the max message size to 2^31 - 10^6 bytes (1MB
%% to allow plenty of leeway for the #basic_message{} and #content{}
%% wrapping the message body).
-define(MAX_MSG_SIZE, 2147383648).
Źródła: https://github.com/rabbitmq/rabbitmq-common/blob/v3.7.21/include/rabbit.hrl#L279
Od wersji 3.8.0 minęło 512 MiB :
%% Max message size is hard limited to 512 MiB.
%% If user configures a greater rabbit.max_message_size,
%% this value is used instead.
-define(MAX_MSG_SIZE, 536870912).
Źródła: https://github.com/rabbitmq/rabbitmq-common/blob/v3.8.0/include/rabbit.hrl#L238