reuse GRV within an http request
diff --git a/src/chttpd/src/chttpd.erl b/src/chttpd/src/chttpd.erl
index 636aad9..0e828f6 100644
--- a/src/chttpd/src/chttpd.erl
+++ b/src/chttpd/src/chttpd.erl
@@ -153,6 +153,7 @@
mochiweb_http:stop(?MODULE).
handle_request(MochiReq0) ->
+ fabric2_fdb:init_grv_cache(),
erlang:put(?REWRITE_COUNT, 0),
MochiReq = couch_httpd_vhost:dispatch_host(MochiReq0),
handle_request_int(MochiReq).
diff --git a/src/fabric/include/fabric2.hrl b/src/fabric/include/fabric2.hrl
index ebbb7c7..62ad9b9 100644
--- a/src/fabric/include/fabric2.hrl
+++ b/src/fabric/include/fabric2.hrl
@@ -76,6 +76,8 @@
-define(PDICT_TX_ID_KEY, '$fabric_tx_id').
-define(PDICT_TX_RES_KEY, '$fabric_tx_result').
-define(PDICT_FOLD_ACC_STATE, '$fabric_fold_acc_state').
+-define(PDICT_GRV_CACHE_ENABLED, '$fabric_grv_cache_enabled').
+-define(PDICT_GRV_CACHE, '$fabric_grv_cache').
% Let's keep these in ascending order
-define(TRANSACTION_TOO_OLD, 1007).
diff --git a/src/fabric/src/fabric2_fdb.erl b/src/fabric/src/fabric2_fdb.erl
index 1690f2f..5394f27 100644
--- a/src/fabric/src/fabric2_fdb.erl
+++ b/src/fabric/src/fabric2_fdb.erl
@@ -19,6 +19,7 @@
transactional/2,
with_snapshot/2,
+ init_grv_cache/0,
create/2,
open/2,
@@ -165,6 +166,43 @@
end).
+init_grv_cache() ->
+ clear_grv_cache(),
+ enable_grv_cache().
+
+
+enable_grv_cache() ->
+ put(?PDICT_GRV_CACHE_ENABLED, true).
+
+
+clear_grv_cache() ->
+ erase(?PDICT_GRV_CACHE).
+
+
+get_grv_cache() ->
+ get(?PDICT_GRV_CACHE).
+
+
+maybe_cache_grv(Tx) ->
+ case get(?PDICT_GRV_CACHE_ENABLED) of
+ undefined ->
+ ok;
+ true ->
+ GRV = erlfdb:wait(erlfdb:get_read_version(Tx)),
+ put(?PDICT_GRV_CACHE, GRV)
+ end.
+
+
+apply_then_clear_grv_cache(Tx) ->
+ case get_grv_cache() of
+ undefined ->
+ ok;
+ GRV ->
+ erlfdb:set_read_version(Tx, GRV),
+ clear_grv_cache()
+ end.
+
+
do_transaction(Fun, LayerPrefix) when is_function(Fun, 1) ->
Db = get_db_handle(),
try
@@ -557,6 +595,7 @@
Future1 = get_info_future(Tx, Future#info_future.db_prefix),
get_info_wait(Future1#info_future{retries = Retries + 1});
error:{erlfdb_error, ?TRANSACTION_TOO_OLD} ->
+ clear_grv_cache(),
ok = erlfdb:reset(Tx),
Future1 = get_info_future(Tx, Future#info_future.db_prefix),
get_info_wait(Future1#info_future{retries = Retries + 1})
@@ -1856,6 +1895,7 @@
restart_fold(Tx, #fold_acc{} = Acc) ->
erase(?PDICT_CHECKED_MD_IS_CURRENT),
+ clear_grv_cache(),
ok = erlfdb:reset(Tx),
case {erase(?PDICT_FOLD_ACC_STATE), Acc#fold_acc.retries} of
@@ -1957,9 +1997,11 @@
execute_transaction(Tx, Fun, LayerPrefix) ->
put(?PDICT_CHECKED_MD_IS_CURRENT, false),
put(?PDICT_CHECKED_DB_IS_CURRENT, false),
+ apply_then_clear_grv_cache(Tx),
Result = Fun(Tx),
case erlfdb:is_read_only(Tx) of
true ->
+ maybe_cache_grv(Tx),
ok;
false ->
erlfdb:set(Tx, get_transaction_id(Tx, LayerPrefix), <<>>),
