feat(router): add unified routing table config option

apps/emqx/src/emqx_schema.erl

@@ -1358,6 +1358,15 @@ fields("broker") ->
                 ref("broker_perf"),
                 #{importance => ?IMPORTANCE_HIDDEN}
             )},
+        {"unified_routing_table",
+            sc(
+                boolean(),
+                #{
+                    default => false,
+                    importance => ?IMPORTANCE_HIDDEN,
+                    desc => ?DESC(broker_unified_routing_table)
+                }
+            )},
         %% FIXME: Need new design for shared subscription group
         {"shared_subscription_group",
             sc(

rel/i18n/emqx_schema.hocon

@@ -1549,6 +1549,12 @@ fields_ws_opts_max_frame_size.label:
 sys_event_messages.desc:
 """Client events messages."""
 
+broker_unified_routing_table.desc:
+"""Enable unified routing table.
+Unified routing table should increase both subscription and routing performance at the cost of slight increase in memory consumption per subscription.
+NOTE: This is an experimental feature.
+NOTE: Full non-rolling cluster restart is needed after enabling or disabling this option for it to take any effect."""
+
 broker_perf_trie_compaction.desc:
 """Enable trie path compaction.
 Enabling it significantly improves wildcard topic subscribe rate, if wildcard topics have unique prefixes like: 'sensor/{{id}}/+/', where ID is unique per subscriber.