nickva commented on a change in pull request #806: FEEDBACK ONLY: Compactor optimize emsort URL: https://github.com/apache/couchdb/pull/806#discussion_r139167681
########## File path: src/couch/src/couch_file.erl ########## @@ -172,21 +175,55 @@ pread_binary(Fd, Pos) -> pread_iolist(Fd, Pos) -> case ioq:call(Fd, {pread_iolist, Pos}, erlang:get(io_priority)) of - {ok, IoList, <<>>} -> - {ok, IoList}; - {ok, IoList, Md5} -> - case crypto:hash(md5, IoList) of - Md5 -> - {ok, IoList}; - _ -> - couch_log:emergency("File corruption in ~p at position ~B", - [Fd, Pos]), - exit({file_corruption, <<"file corruption">>}) - end; - Error -> - Error + {ok, IoList, Md5} -> + {ok, verify_md5(Fd, Pos, IoList, Md5)}; + Error -> + Error end. + +pread_terms(Fd, PosList) -> + {ok, Bins} = pread_binaries(Fd, PosList), + Terms = lists:map(fun(Bin) -> + couch_compress:decompress(Bin) + end, Bins), + {ok, Terms}. + + +pread_binaries(Fd, PosList) -> + {ok, Data} = pread_iolists(Fd, PosList), + {ok, lists:map(fun erlang:iolist_to_binary/1, Data)}. + + +pread_iolists(Fd, PosList) -> + case ioq:call(Fd, {pread_iolists, PosList}, erlang:get(io_priority)) of + {ok, DataMd5s} -> + Data = lists:zipwith(fun(Pos, {IoList, Md5}) -> + verify_md5(Fd, Pos, IoList, Md5) + end, PosList, DataMd5s), + {ok, Data}; + Error -> + Error + end. + + +append_terms(Fd, Terms) -> + append_terms(Fd, Terms, []). + + +append_terms(Fd, Terms, Options) -> + Comp = couch_util:get_value(compression, Options, ?DEFAULT_COMPRESSION), Review comment: btree's write_node would grab the compression option from the #btree record which would still be snappy, but most of it will be provided in couch_btree:open() which would be read from the config file `couch_compress:get_compression_method()` and that should be whatever user specified. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services