WIP: use atoms to speed up hash lookup of shared cursors.

c_src/wterl.c

@@ -51,7 +51,7 @@ static ErlNifResourceType *wterl_conn_RESOURCE;
 static ErlNifResourceType *wterl_cursor_RESOURCE;
 
 /* Generators for 'cursors' a named, type-specific hash table functions. */
-KHASH_MAP_INIT_STR(cursors, WT_CURSOR*);
+KHASH_INIT(cursors, ERL_NIF_TERM, WT_CURSOR*, 1, kh_int_hash_func, enif_is_identical);
 
 /**
  * We will have exactly one (1) WterlCtx for each async worker thread.  As
@@ -305,11 +305,9 @@ __close_all_sessions(WterlConnHandle *conn_handle)
             for (itr = kh_begin(h); itr != kh_end(h); ++itr) {
                 if (kh_exist(h, itr)) {
                     WT_CURSOR *cursor = kh_val(h, itr);
-                    char *key = (char *)kh_key(h, itr);
                     cursor->close(cursor);
-                    kh_del(cursors, h, itr);
-                    enif_free(key);
                     kh_value(h, itr) = NULL;
+                    kh_del(cursors, h, itr);
                 }
             }
             kh_destroy(cursors, h);
@@ -325,7 +323,7 @@ __close_all_sessions(WterlConnHandle *conn_handle)
  * Note: always call within enif_mutex_lock/unlock(conn_handle->contexts_mutex)
  */
 void
-__close_cursors_on(WterlConnHandle *conn_handle, const char *uri)
+__close_cursors_on(WterlConnHandle *conn_handle, ERL_NIF_TERM key)
 {
     int i;
 
@@ -333,14 +331,12 @@ __close_cursors_on(WterlConnHandle *conn_handle, const char *uri)
         WterlCtx *ctx = &conn_handle->contexts[i];
         if (ctx->session != NULL) {
             khash_t(cursors) *h = ctx->cursors;
-            khiter_t itr = kh_get(cursors, h, (char *)uri);
+            khiter_t itr = kh_get(cursors, h, key);
             if (itr != kh_end(h)) {
                 WT_CURSOR *cursor = kh_value(h, itr);
-                char *key = (char *)kh_key(h, itr);
                 cursor->close(cursor);
-                kh_del(cursors, h, itr);
-                enif_free(key);
                 kh_value(h, itr) = NULL;
+                kh_del(cursors, h, itr);
             }
         }
     }
@@ -368,7 +364,7 @@ __retain_cursor(WterlConnHandle *conn_handle, unsigned int worker_id, const char
     }
 
     h = ctx->cursors;
-    itr = kh_get(cursors, h, (char *)uri);
+    itr = kh_get(cursors, h, key);
     if (itr != kh_end(h)) {
         // key exists in hash table, retrieve it
         *cursor = (WT_CURSOR*)kh_value(h, itr);
@@ -570,8 +566,8 @@ ASYNC_NIF_DECL(
     itr = kh_get(conns, h, conn);
     if (itr != kh_end(h)) {
         /* key exists in table (as expected) delete it */
-        kh_del(conns, h, itr);
         kh_value(h, itr) = NULL;
+        kh_del(conns, h, itr);
     }
     enif_mutex_unlock(args->priv->conns_mutex);
     enif_mutex_unlock(args->conn_handle->contexts_mutex);
@@ -2175,11 +2171,9 @@ on_unload(ErlNifEnv *env, void *priv_data)
               for (itr_cursors = kh_begin(h); itr_cursors != kh_end(h); ++itr_cursors) {
                 if (kh_exist(h, itr_cursors)) {
                   WT_CURSOR *cursor = kh_val(h, itr_cursors);
-                  char *key = (char *)kh_key(h, itr_cursors);
                   cursor->close(cursor);
-                  kh_del(cursors, h, itr_cursors);
-                  enif_free(key);
                   kh_value(h, itr_cursors) = NULL;
+                  kh_del(cursors, h, itr_cursors);
                 }
               }
               kh_destroy(cursors, h);

src/riak_kv_wterl_backend.erl

@@ -50,7 +50,7 @@
 %%-define(CAPABILITIES, [async_fold, indexes]).
 -define(CAPABILITIES, [async_fold]).
 
--record(state, {table :: string(),
+-record(state, {table :: atom(), % Atoms aka int's are easier to hash
                 type :: string(),
                 connection :: wterl:connection(),
                 is_empty_cursor :: wterl:cursor(),
@@ -107,7 +107,7 @@ start(Partition, Config) ->
                         "lsm"
                 end,
             {ok, Connection} = establish_connection(Config, Type),
-            Table = Type ++ ":" ++ integer_to_list(Partition),
+            TableUri = Type ++ ":" ++ integer_to_list(Partition),
             Compressor =
                 case wterl:config_value(block_compressor, Config, "snappy") of
                     {block_compressor, "snappy"}=C -> [C];
@@ -133,7 +133,8 @@ start(Partition, Config) ->
                     "table" ->
                         Compressor
                 end,
-            case wterl:create(Connection, Table, TableOpts) of
+            Table = list_to_atom(TableUri),
+            case wterl:create(Connection, TableUri, TableOpts) of
                 ok ->
                     case establish_utility_cursors(Connection, Table) of
                         {ok, IsEmptyCursor, StatusCursor} ->

src/wterl.erl

@@ -134,71 +134,71 @@ connection_close(ConnRef) ->
 conn_close_nif(_AsyncRef, _ConnRef) ->
     ?nif_stub.
 
--spec create(connection(), string()) -> ok | {error, term()}.
+-spec create(connection(), atom()) -> ok | {error, term()}.
--spec create(connection(), string(), config_list()) -> ok | {error, term()}.
+-spec create(connection(), atom(), config_list()) -> ok | {error, term()}.
 create(Ref, Name) ->
     create(Ref, Name, []).
 create(Ref, Name, Config) ->
     ?ASYNC_NIF_CALL(fun create_nif/4, [Ref, Name, config_to_bin(Config)]).
 
--spec create_nif(reference(), connection(), string(), config()) -> ok | {error, term()}.
+-spec create_nif(reference(), connection(), atom(), config()) -> ok | {error, term()}.
 create_nif(_AsyncNif, _Ref, _Name, _Config) ->
     ?nif_stub.
 
--spec drop(connection(), string()) -> ok | {error, term()}.
+-spec drop(connection(), atom()) -> ok | {error, term()}.
--spec drop(connection(), string(), config_list()) -> ok | {error, term()}.
+-spec drop(connection(), atom(), config_list()) -> ok | {error, term()}.
 drop(Ref, Name) ->
     drop(Ref, Name, [{force, true}]).
 drop(Ref, Name, Config) ->
     ?ASYNC_NIF_CALL(fun drop_nif/4, [Ref, Name, config_to_bin(Config)]).
 
--spec drop_nif(reference(), connection(), string(), config()) -> ok | {error, term()}.
+-spec drop_nif(reference(), connection(), atom(), config()) -> ok | {error, term()}.
 drop_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
--spec delete(connection(), string(), key()) -> ok | {error, term()}.
+-spec delete(connection(), atom(), key()) -> ok | {error, term()}.
 delete(Ref, Table, Key) ->
     ?ASYNC_NIF_CALL(fun delete_nif/4, [Ref, Table, Key]).
 
--spec delete_nif(reference(), connection(), string(), key()) -> ok | {error, term()}.
+-spec delete_nif(reference(), connection(), atom(), key()) -> ok | {error, term()}.
 delete_nif(_AsyncRef, _Ref, _Table, _Key) ->
     ?nif_stub.
 
--spec get(connection(), string(), key()) -> {ok, value()} | not_found | {error, term()}.
+-spec get(connection(), atom(), key()) -> {ok, value()} | not_found | {error, term()}.
 get(Ref, Table, Key) ->
     ?ASYNC_NIF_CALL(fun get_nif/4, [Ref, Table, Key]).
 
--spec get_nif(reference(), connection(), string(), key()) -> {ok, value()} | not_found | {error, term()}.
+-spec get_nif(reference(), connection(), atom(), key()) -> {ok, value()} | not_found | {error, term()}.
 get_nif(_AsyncRef, _Ref, _Table, _Key) ->
     ?nif_stub.
 
--spec put(connection(), string(), key(), value()) -> ok | {error, term()}.
+-spec put(connection(), atom(), key(), value()) -> ok | {error, term()}.
 put(Ref, Table, Key, Value) ->
     ?ASYNC_NIF_CALL(fun put_nif/5, [Ref, Table, Key, Value]).
 
--spec put_nif(reference(), connection(), string(), key(), value()) -> ok | {error, term()}.
+-spec put_nif(reference(), connection(), atom(), key(), value()) -> ok | {error, term()}.
 put_nif(_AsyncRef, _Ref, _Table, _Key, _Value) ->
     ?nif_stub.
 
--spec rename(connection(), string(), string()) -> ok | {error, term()}.
+-spec rename(connection(), atom(), string()) -> ok | {error, term()}.
--spec rename(connection(), string(), string(), config_list()) -> ok | {error, term()}.
+-spec rename(connection(), atom(), string(), config_list()) -> ok | {error, term()}.
 rename(Ref, OldName, NewName) ->
     rename(Ref, OldName, NewName, []).
 rename(Ref, OldName, NewName, Config) ->
     ?ASYNC_NIF_CALL(fun rename_nif/5, [Ref, OldName, NewName, config_to_bin(Config)]).
 
--spec rename_nif(reference(), connection(), string(), string(), config()) -> ok | {error, term()}.
+-spec rename_nif(reference(), connection(), atom(), string(), config()) -> ok | {error, term()}.
 rename_nif(_AsyncRef, _Ref, _OldName, _NewName, _Config) ->
     ?nif_stub.
 
--spec salvage(connection(), string()) -> ok | {error, term()}.
+-spec salvage(connection(), atom()) -> ok | {error, term()}.
--spec salvage(connection(), string(), config_list()) -> ok | {error, term()}.
+-spec salvage(connection(), atom(), config_list()) -> ok | {error, term()}.
 salvage(Ref, Name) ->
     salvage(Ref, Name, []).
 salvage(Ref, Name, Config) ->
     ?ASYNC_NIF_CALL(fun salvage_nif/4, [Ref, Name, config_to_bin(Config)]).
 
--spec salvage_nif(reference(), connection(), string(), config()) -> ok | {error, term()}.
+-spec salvage_nif(reference(), connection(), atom(), config()) -> ok | {error, term()}.
 salvage_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
@@ -213,10 +213,10 @@ checkpoint(Ref, Config) ->
 checkpoint_nif(_AsyncRef, _Ref, _Config) ->
     ?nif_stub.
 
--spec truncate(connection(), string()) -> ok | {error, term()}.
+-spec truncate(connection(), atom()) -> ok | {error, term()}.
--spec truncate(connection(), string(), config_list()) -> ok | {error, term()}.
+-spec truncate(connection(), atom(), config_list()) -> ok | {error, term()}.
--spec truncate(connection(), string(), binary() | first, binary() | last) -> ok | {error, term()}.
+-spec truncate(connection(), atom(), binary() | first, binary() | last) -> ok | {error, term()}.
--spec truncate(connection(), string(), binary() | first, binary() | last, config()) -> ok | {error, term()}.
+-spec truncate(connection(), atom(), binary() | first, binary() | last, config()) -> ok | {error, term()}.
 truncate(Ref, Name) ->
     truncate(Ref, Name, first, last, []).
 truncate(Ref, Name, Config) ->
@@ -226,40 +226,40 @@ truncate(Ref, Name, Start, Stop) ->
 truncate(Ref, Name, Start, Stop, Config) ->
     ?ASYNC_NIF_CALL(fun truncate_nif/6, [Ref, Name, Start, Stop, config_to_bin(Config)]).
 
--spec truncate_nif(reference(), connection(), string(), cursor() | first, cursor() | last, config()) -> ok | {error, term()}.
+-spec truncate_nif(reference(), connection(), atom(), cursor() | first, cursor() | last, config()) -> ok | {error, term()}.
 truncate_nif(_AsyncRef, _Ref, _Name, _Start, _Stop, _Config) ->
     ?nif_stub.
 
--spec upgrade(connection(), string()) -> ok | {error, term()}.
+-spec upgrade(connection(), atom()) -> ok | {error, term()}.
--spec upgrade(connection(), string(), config_list()) -> ok | {error, term()}.
+-spec upgrade(connection(), atom(), config_list()) -> ok | {error, term()}.
 upgrade(Ref, Name) ->
     upgrade(Ref, Name, []).
 upgrade(Ref, Name, Config) ->
     ?ASYNC_NIF_CALL(fun upgrade_nif/4, [Ref, Name, config_to_bin(Config)]).
 
--spec upgrade_nif(reference(), connection(), string(), config()) -> ok | {error, term()}.
+-spec upgrade_nif(reference(), connection(), atom(), config()) -> ok | {error, term()}.
 upgrade_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
--spec verify(connection(), string()) -> ok | {error, term()}.
+-spec verify(connection(), atom()) -> ok | {error, term()}.
--spec verify(connection(), string(), config_list()) -> ok | {error, term()}.
+-spec verify(connection(), atom(), config_list()) -> ok | {error, term()}.
 verify(Ref, Name) ->
     verify(Ref, Name, []).
 verify(Ref, Name, Config) ->
     ?ASYNC_NIF_CALL(fun verify_nif/4, [Ref, Name, config_to_bin(Config)]).
 
--spec verify_nif(reference(), connection(), string(), config()) -> ok | {error, term()}.
+-spec verify_nif(reference(), connection(), atom(), config()) -> ok | {error, term()}.
 verify_nif(_AsyncRef, _Ref, _Name, _Config) ->
     ?nif_stub.
 
--spec cursor_open(connection(), string()) -> {ok, cursor()} | {error, term()}.
+-spec cursor_open(connection(), atom()) -> {ok, cursor()} | {error, term()}.
--spec cursor_open(connection(), string(), config_list()) -> {ok, cursor()} | {error, term()}.
+-spec cursor_open(connection(), atom(), config_list()) -> {ok, cursor()} | {error, term()}.
 cursor_open(Ref, Table) ->
     cursor_open(Ref, Table, []).
 cursor_open(Ref, Table, Config) ->
     ?ASYNC_NIF_CALL(fun cursor_open_nif/4, [Ref, Table, config_to_bin(Config)]).
 
--spec cursor_open_nif(reference(), connection(), string(), config()) -> {ok, cursor()} | {error, term()}.
+-spec cursor_open_nif(reference(), connection(), atom(), config()) -> {ok, cursor()} | {error, term()}.
 cursor_open_nif(_AsyncRef, _Ref, _Table, _Config) ->
     ?nif_stub.