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Diffstat (limited to 'deps/fabric/src/fabric_view_reduce.erl')
-rw-r--r-- | deps/fabric/src/fabric_view_reduce.erl | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/deps/fabric/src/fabric_view_reduce.erl b/deps/fabric/src/fabric_view_reduce.erl new file mode 100644 index 00000000..58438573 --- /dev/null +++ b/deps/fabric/src/fabric_view_reduce.erl @@ -0,0 +1,114 @@ +% Copyright 2010 Cloudant +% +% Licensed under the Apache License, Version 2.0 (the "License"); you may not +% use this file except in compliance with the License. You may obtain a copy of +% the License at +% +% http://www.apache.org/licenses/LICENSE-2.0 +% +% Unless required by applicable law or agreed to in writing, software +% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT +% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the +% License for the specific language governing permissions and limitations under +% the License. + +-module(fabric_view_reduce). + +-export([go/6]). + +-include("fabric.hrl"). +-include_lib("mem3/include/mem3.hrl"). +-include_lib("couch/include/couch_db.hrl"). + +go(DbName, GroupId, View, Args, Callback, Acc0) when is_binary(GroupId) -> + {ok, DDoc} = fabric:open_doc(DbName, <<"_design/", GroupId/binary>>, []), + go(DbName, DDoc, View, Args, Callback, Acc0); + +go(DbName, DDoc, VName, Args, Callback, Acc0) -> + #group{def_lang=Lang, views=Views} = Group = + couch_view_group:design_doc_to_view_group(DDoc), + {NthRed, View} = fabric_view:extract_view(nil, VName, Views, reduce), + {VName, RedSrc} = lists:nth(NthRed, View#view.reduce_funs), + Workers = lists:map(fun(#shard{name=Name, node=N} = Shard) -> + Ref = rexi:cast(N, {fabric_rpc, reduce_view, [Name,Group,VName,Args]}), + Shard#shard{ref = Ref} + end, fabric_view:get_shards(DbName, Args)), + RexiMon = fabric_util:create_monitors(Workers), + BufferSize = couch_config:get("fabric", "reduce_buffer_size", "20"), + #view_query_args{limit = Limit, skip = Skip} = Args, + State = #collector{ + db_name = DbName, + query_args = Args, + callback = Callback, + buffer_size = list_to_integer(BufferSize), + counters = fabric_dict:init(Workers, 0), + keys = Args#view_query_args.keys, + skip = Skip, + limit = Limit, + lang = Group#group.def_lang, + os_proc = couch_query_servers:get_os_process(Lang), + reducer = RedSrc, + rows = dict:new(), + user_acc = Acc0 + }, + try rexi_utils:recv(Workers, #shard.ref, fun handle_message/3, + State, infinity, 1000 * 60 * 60) of + {ok, NewState} -> + {ok, NewState#collector.user_acc}; + {timeout, NewState} -> + Callback({error, timeout}, NewState#collector.user_acc); + {error, Resp} -> + {ok, Resp} + after + rexi_monitor:stop(RexiMon), + fabric_util:cleanup(Workers), + catch couch_query_servers:ret_os_process(State#collector.os_proc) + end. + +handle_message({rexi_DOWN, _, {_, NodeRef}, _}, _, State) -> + fabric_view:remove_down_shards(State, NodeRef); + +handle_message({rexi_EXIT, Reason}, Worker, State) -> + #collector{callback=Callback, counters=Counters0, user_acc=Acc} = State, + Counters = fabric_dict:erase(Worker, Counters0), + case fabric_view:is_progress_possible(Counters) of + true -> + {ok, State#collector{counters = Counters}}; + false -> + {ok, Resp} = Callback({error, fabric_util:error_info(Reason)}, Acc), + {error, Resp} + end; + +handle_message(#view_row{key=Key} = Row, {Worker, From}, State) -> + #collector{counters = Counters0, rows = Rows0} = State, + case fabric_dict:lookup_element(Worker, Counters0) of + undefined -> + % this worker lost the race with other partition copies, terminate it + gen_server:reply(From, stop), + {ok, State}; + _ -> + Rows = dict:append(Key, Row#view_row{worker=Worker}, Rows0), + C1 = fabric_dict:update_counter(Worker, 1, Counters0), + % TODO time this call, if slow don't do it every time + C2 = fabric_view:remove_overlapping_shards(Worker, C1), + State1 = State#collector{rows=Rows, counters=C2}, + State2 = fabric_view:maybe_pause_worker(Worker, From, State1), + fabric_view:maybe_send_row(State2) + end; + +handle_message(complete, Worker, State) -> + C1 = fabric_dict:update_counter(Worker, 1, State#collector.counters), + C2 = fabric_view:remove_overlapping_shards(Worker, C1), + fabric_view:maybe_send_row(State#collector{counters = C2}). + +complete_worker_test() -> + Shards = + mem3_util:create_partition_map("foo",3,3,[node(),node(),node()]), + Workers = lists:map(fun(#shard{} = Shard) -> + Ref = make_ref(), + Shard#shard{ref = Ref} + end, + Shards), + State = #collector{counters=fabric_dict:init(Workers,0)}, + {ok, NewState} = handle_message(complete, lists:nth(2,Workers), State), + ?assertEqual(orddict:size(NewState#collector.counters),length(Workers) - 2). |