Optimize db:get_by_indices by not fetching entry and implementing index:getrange

1 files changed, 7 insertions, 5 deletions

diff --git a/src/db.erl b/src/db.erl
index fade7ce..f7c2057 100644
--- a/src/db.erl
+++ b/src/db.erl
@@ -129,6 +129,9 @@ index_for_leafhash(LeafHash) ->
 leafhash_for_index(Index) ->
     index:get(index_path(), Index).
 
+leafhash_for_indices(Start, End) ->
+    index:getrange(index_path(), Start, End).
+
 leafhash_for_entryhash(EntryHash) ->
     perm:readfile(entryhash_root_path(), EntryHash).
 
@@ -138,11 +141,10 @@ get_by_indices_helper(Start, End) ->
     EndBound = min(End, size() - 1),
     case Start =< EndBound of
         true ->
-            lists:map(fun (Index) ->
-                              LeafHash = leafhash_for_index(Index),
-                              Entry = entry_for_leafhash(LeafHash),
-                              {Index, LeafHash, Entry}
-                      end, lists:seq(Start, EndBound));
+            lists:map(fun ({LeafHash, Index}) ->
+                              {Index, LeafHash, notfetched}
+                      end, lists:zip(leafhash_for_indices(Start, EndBound),
+                                     lists:seq(Start, EndBound)));
         false ->
             []
     end.