Use 8k iobuf limit for aws

PUBLISHED_FROM=971951e1eeb82078b986cd6e25e52cfc1ccef286

Author: cpq

mos.yml

@@ -27,6 +27,7 @@ config_schema:
   - ["mqtt.will_topic", "s", "", {title: "Will topic"}]
   - ["mqtt.will_message", "s", "", {title: "Will message"}]
   - ["mqtt.max_qos", "i", 2, {title: "Limit QoS of outgoing messages to at most this"}]
+  - ["mqtt.recv_mbuf_limit", "i", 3072, {title: "Limit recv buffer size"}]
   - ["debug.stdout_topic", "s", "", {title: "MQTT topic to publish STDOUT to"}]
   - ["debug.stderr_topic", "s", "", {title: "MQTT topic to publish STDERR to"}]
 cdefs:

src/mgos_mqtt.c

@@ -313,6 +313,7 @@ bool mgos_mqtt_global_connect(void) {
                           NULL, opts);
   if (s_conn != NULL) {
     mg_set_protocol_mqtt(s_conn);
+    s_conn->recv_mbuf_limit = mgos_sys_config_get_mqtt_recv_mbuf_limit();
   } else {
     ret = false;
   }