Generalized GC (corrected base) (#4106)

* Generalized GC (corrected base)

* Add GC doc to mkdocs.yml

apps/aechannel/src/aesc_state_tree.erl

@@ -17,7 +17,8 @@
          mtree_iterator/1,
          new_with_backend/1,
          new_with_dirty_backend/1,
-         root_hash/1]).
+         root_hash/1,
+         db/1]).
 
 -export([ from_binary_without_backend/1
         , to_binary_without_backend/1
@@ -91,6 +92,10 @@ lookup(PubKey, Tree) ->
 root_hash(Tree) ->
     aeu_mtrees:root_hash(Tree).
 
+-spec db(tree()) -> {'ok', aeu_mp_trees:db()}.
+db(Tree) ->
+    aeu_mtrees:db(Tree).
+
 -spec to_binary_without_backend(tree()) -> binary().
 to_binary_without_backend(Tree) ->
     Bin = aeu_mtrees:serialize(Tree),

apps/aecontract/src/aect_call_state_tree.erl

@@ -20,7 +20,8 @@
         , iterator/1
         , prune/2
         , prune_without_backend/1
-        , root_hash/1]).
+        , root_hash/1
+        , db/1 ]).
 
 -export([ from_binary_without_backend/1
         , to_binary_without_backend/1
@@ -88,12 +89,20 @@ new_with_dirty_backend(Hash) ->
 %% Calls and return values are only kept for one block.
 -spec prune(aec_blocks:height(), aec_trees:trees()) -> aec_trees:trees().
 prune(_,Trees) ->
-    aec_trees:set_calls(Trees, empty_with_backend()).
+    CTree = aec_trees:calls(Trees),
+    Empty = case has_backend(CTree) of
+                true  -> empty_with_backend();
+                false -> empty()
+            end,
+    aec_trees:set_calls(Trees, Empty).
 
 -spec prune_without_backend(aec_trees:trees()) -> aec_trees:trees().
 prune_without_backend(Trees) ->
     aec_trees:set_calls(Trees, empty()).
 
+has_backend(#call_tree{calls = CtTree}) ->
+    aeu_mtrees:has_backend(CtTree).
+
 -spec insert_call(aect_call:call(), tree()) -> tree().
 insert_call(Call, Tree) ->
     CtCallId = aect_call:ct_call_id(Call),
@@ -138,6 +147,10 @@ call_id(<<_:?PUB_SIZE/unit:8, CallId/binary>> = _CallTreeId) ->
 root_hash(#call_tree{calls = CtTree}) ->
     aeu_mtrees:root_hash(CtTree).
 
+-spec db(tree()) -> {ok, aeu_mp_trees:db()}.
+db(#call_tree{calls = CtTree}) ->
+    aeu_mtrees:db(CtTree).
+
 %% -- Commit to db --
 
 -spec commit_to_db(tree()) -> tree().

apps/aecontract/src/aect_state_tree.erl

@@ -28,7 +28,8 @@
         , new_with_backend/1
         , new_with_dirty_backend/1
         , gc_cache/1
-        , root_hash/1]).
+        , root_hash/1
+        , db/1 ]).
 
 %% API - Proof of inclusion
 -export([ add_poi/3
@@ -265,6 +266,10 @@ lookup_contract_with_code(Pubkey, Tree, Options) ->
 root_hash(#contract_tree{contracts = CtTree}) ->
     aeu_mtrees:root_hash(CtTree).
 
+-spec db(tree()) -> {ok, aeu_mp_trees:db()}.
+db(#contract_tree{contracts = CtTree}) ->
+    aeu_mtrees:db(CtTree).
+
 -spec add_poi(aect_contracts:pubkey(), aect_state_tree:tree(), aec_poi:poi()) ->
                      {'ok', aec_poi:poi()}
                    | {'error', 'not_present' | 'wrong_root_hash'}.

apps/aecontract/test/aect_test_utils.erl

@@ -77,7 +77,7 @@ new_state() ->
     #{}.
 
 trees(#{} = S) ->
-    maps:get(trees, S, aec_trees:new()).
+    maps:get(trees, S, aec_trees:new_without_backend()).
 
 set_trees(Trees, S) ->
     S#{trees => Trees}.

apps/aecore/src/aec_chain_state.erl

@@ -1484,7 +1484,5 @@ key_headers_height_store_migration_step(Time, N, {TimeRead, {Headers, Cont}}) ->
     ).
 
 is_gc_disabled() ->
-    case aec_db_gc:config() of
-        #{enabled := Bool} when is_boolean(Bool) ->
-            Bool
-    end.
+    [Bool] = aec_db_gc:info([enabled]),
+    Bool.

apps/aecore/src/aec_conductor.erl

@@ -1409,7 +1409,7 @@ handle_successfully_added_block(Block, Hash, true, PrevKeyHeader, Events, State,
                     ok; %% Don't spend time when we are the leader.
                 false ->
                     aec_tx_pool:garbage_collect(),
-                    [ maybe_garbage_collect_accounts() || BlockType == key ]
+                    [ maybe_garbage_collect(NewTopBlock) || BlockType == key ]
             end,
             {ok, setup_loop(State2, true, IsLeader, Origin)}
     end.
@@ -1506,13 +1506,18 @@ get_pending_key_block(TopHash, State) ->
 %%
 %% To avoid starting of the GC process just for EUNIT
 -ifdef(EUNIT).
-maybe_garbage_collect_accounts() -> nop.
+maybe_garbage_collect(_) -> nop.
 -else.
 
 %% This should be called when there are no processes modifying the block state
 %% (e.g. aec_conductor on specific places)
-maybe_garbage_collect_accounts() ->
-    gen_statem:call(aec_db_gc, maybe_garbage_collect).
+maybe_garbage_collect(Block) ->
+    T0 = erlang:system_time(microsecond),
+    Header = aec_blocks:to_header(Block),
+    Res = aec_db_gc:maybe_garbage_collect(Header),
+    T1 = erlang:system_time(microsecond),
+    lager:debug("Result -> ~p (time: ~p us)", [Res, T1-T0]),
+    Res.
 -endif.
 
 consensus_module(#state{ consensus = #consensus{consensus_module =