Read db size from sth file and cache

1 files changed, 16 insertions, 8 deletions

diff --git a/src/db.erl b/src/db.erl
index daa581c..707c8d3 100644
--- a/src/db.erl
+++ b/src/db.erl
@@ -6,6 +6,7 @@
 
 %% API.
 -export([start_link/0, stop/0]).
+-export([create_size_table/0]).
 -export([add/2, add_entryhash/2, add_index_nosync/2, set_treesize/1, size/0]).
 -export([get_by_index/1, get_by_indices/3, get_by_leaf_hash/1]).
 -export([get_by_entry_hash/1, entry_for_leafhash/1, leafhash_for_index/1]).
@@ -19,8 +20,11 @@
 -include_lib("stdlib/include/qlc.hrl").
 -include("db.hrl").
 
+-define(DB_SIZE_TABLE, db_size).
+
 size() ->
-    binary_to_integer(atomic:readfile(treesize_path())).
+    [{_, Size}] = ets:lookup(?DB_SIZE_TABLE, db_size),
+    Size.
 
 indexsize() ->
     index:indexsize(index_path()).
@@ -28,6 +32,15 @@ indexsize() ->
 init(_Args) ->
     {ok, []}.
 
+create_size_table() ->
+    case ets:info(?DB_SIZE_TABLE) of
+	undefined ->
+	    ok;
+	_ ->
+	    ets:delete(?DB_SIZE_TABLE)
+    end,
+    ets:new(?DB_SIZE_TABLE, [set, public, named_table]).
+
 start_link() ->
     gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).
 
@@ -55,7 +68,8 @@ add_index_nosync(LeafHash, Index) ->
 
 -spec set_treesize(non_neg_integer()) -> ok.
 set_treesize(Size) ->
-    ok = atomic:replacefile(treesize_path(), integer_to_binary(Size)).
+    true = ets:insert(?DB_SIZE_TABLE, {db_size, Size}),
+    ok.
 
 -spec get_by_indices(integer(), integer(), {sorted, true|false}) ->
                             [{non_neg_integer(), binary(), binary()}].
@@ -138,12 +152,6 @@ entryhash_root_path() ->
     {ok, Value} = application:get_env(plop, entryhash_root_path),
     Value.
 
-% File that stores tree size
-treesize_path() ->
-    {ok, Value} = application:get_env(plop, treesize_path),
-    Value.
-
-
 entry_for_leafhash(LeafHash) ->
     perm:readfile(entry_root_path(), LeafHash).