choice of uuid algos for better insert perf. Closes COUCHDB-465. Thanks rnewson, bitdiddle

git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@813051 13f79535-47bb-0310-9956-ffa450edef68

7 files changed, 13 insertions, 15 deletions

diff --git a/src/couchdb/Makefile.am b/src/couchdb/Makefile.am
index 017dc169..97d8a3b0 100644
--- a/src/couchdb/Makefile.am
+++ b/src/couchdb/Makefile.am
@@ -101,6 +101,7 @@ source_files = \
     couch_stream.erl \
     couch_task_status.erl \
     couch_util.erl \
+    couch_uuids.erl \
     couch_view.erl \
     couch_view_compactor.erl \
     couch_view_updater.erl \
@@ -157,6 +158,7 @@ compiled_files = \
     couch_stream.beam \
     couch_task_status.beam \
     couch_util.beam \
+    couch_uuids.beam \
     couch_view.beam \
     couch_view_compactor.beam \
     couch_view_updater.beam \
diff --git a/src/couchdb/couch_httpd_auth.erl b/src/couchdb/couch_httpd_auth.erl
index c77376b2..1c1ad0a9 100644
--- a/src/couchdb/couch_httpd_auth.erl
+++ b/src/couchdb/couch_httpd_auth.erl
@@ -381,9 +381,9 @@ create_user_req(#httpd{method='POST', mochi_req=MochiReq}=Req, Db) ->
             [?l2b(R) || R <- Roles]
         end,
             
-        UserSalt = couch_util:new_uuid(),
+        UserSalt = couch_uuids:random(),
         PasswordHash = hash_password(Password, UserSalt),
-        DocId = couch_util:new_uuid(),
+        DocId = couch_uuids:random(),
         {ok, UserDoc} = user_doc(DocId, UserName, UserSalt, PasswordHash, Email, Active, Roles1),
         {ok, _Rev} = couch_db:update_doc(Db, UserDoc, []),
         ?LOG_DEBUG("User ~s (~s) with password, ~s created.", [?b2l(UserName), ?b2l(DocId), ?b2l(Password)]),
diff --git a/src/couchdb/couch_httpd_db.erl b/src/couchdb/couch_httpd_db.erl
index 1a18c4ba..0f3835ae 100644
--- a/src/couchdb/couch_httpd_db.erl
+++ b/src/couchdb/couch_httpd_db.erl
@@ -308,7 +308,7 @@ db_req(#httpd{method='POST',path_parts=[DbName]}=Req, Db) ->
     Doc = couch_doc:from_json_obj(couch_httpd:json_body(Req)),
     Doc2 = case Doc#doc.id of
         <<"">> ->
-            Doc#doc{id=couch_util:new_uuid(), revs={0, []}};
+            Doc#doc{id=couch_uuids:new(), revs={0, []}};
         _ ->
             Doc
     end,
@@ -385,7 +385,7 @@ db_req(#httpd{method='POST',path_parts=[_,<<"_bulk_docs">>]}=Req, Db) ->
                 Doc = couch_doc:from_json_obj(JsonObj),
                 validate_attachment_names(Doc),
                 Id = case Doc#doc.id of
-                    <<>> -> couch_util:new_uuid();
+                    <<>> -> couch_uuids:new();
                     Id0 -> Id0
                 end,
                 case proplists:get_value(<<"_rev">>, ObjProps) of
diff --git a/src/couchdb/couch_httpd_misc_handlers.erl b/src/couchdb/couch_httpd_misc_handlers.erl
index c3c5b37a..7f5573ff 100644
--- a/src/couchdb/couch_httpd_misc_handlers.erl
+++ b/src/couchdb/couch_httpd_misc_handlers.erl
@@ -108,11 +108,10 @@ handle_uuids_req(#httpd{method='GET'}=Req) ->
     Count = list_to_integer(couch_httpd:qs_value(Req, "count", "1")),
     CacheBustingHeaders = [{"Date", httpd_util:rfc1123_date()},
                            {"Cache-Control", "no-cache"},
-                           {"Expires", "Fri, 01 Jan 1990 00:00:00 GMT"},  % Past date, ON PURPOSE!
+                           % Past date, ON PURPOSE!
+                           {"Expires", "Fri, 01 Jan 1990 00:00:00 GMT"},
                            {"Pragma", "no-cache"}],
-    % generate the uuids
-    UUIDs = [ couch_util:new_uuid() || _ <- lists:seq(1,Count)],
-    % send a JSON response
+    UUIDs = [couch_uuids:new() || _ <- lists:seq(1, Count)],
     send_json(Req, 200, CacheBustingHeaders, {[{<<"uuids">>, UUIDs}]});
 handle_uuids_req(Req) ->
     send_method_not_allowed(Req, "GET").
diff --git a/src/couchdb/couch_rep.erl b/src/couchdb/couch_rep.erl
index bcd1807c..c2f691eb 100644
--- a/src/couchdb/couch_rep.erl
+++ b/src/couchdb/couch_rep.erl
@@ -470,7 +470,7 @@ do_checkpoint(State) ->
             "replication is redone and documents reexamined.", []),
         StartSeqNum
     end,
-    SessionId = couch_util:new_uuid(),
+    SessionId = couch_uuids:random(),
     NewHistoryEntry = {[
         {<<"session_id">>, SessionId},
         {<<"start_time">>, list_to_binary(ReplicationStartTime)},
diff --git a/src/couchdb/couch_server.erl b/src/couchdb/couch_server.erl
index f407acf0..8fab42f1 100644
--- a/src/couchdb/couch_server.erl
+++ b/src/couchdb/couch_server.erl
@@ -99,7 +99,7 @@ hash_admin_passwords() ->
         fun({_User, "-hashed-" ++ _}) ->
             ok; % already hashed
         ({User, ClearPassword}) ->
-            Salt = ?b2l(couch_util:new_uuid()),
+            Salt = ?b2l(couch_uuids:random()),
             Hashed = couch_util:to_hex(crypto:sha(ClearPassword ++ Salt)),
             couch_config:set("admins", User, "-hashed-" ++ Hashed ++ "," ++ Salt)
         end, couch_config:get("admins")).
diff --git a/src/couchdb/couch_util.erl b/src/couchdb/couch_util.erl
index d967b433..088fde85 100644
--- a/src/couchdb/couch_util.erl
+++ b/src/couchdb/couch_util.erl
@@ -14,7 +14,7 @@
 
 -export([start_driver/1,terminate_linked/1]).
 -export([should_flush/0, should_flush/1, to_existing_atom/1]).
--export([new_uuid/0, rand32/0, implode/2, collate/2, collate/3]).
+-export([rand32/0, implode/2, collate/2, collate/3]).
 -export([abs_pathname/1,abs_pathname/2, trim/1, ascii_lower/1]).
 -export([encodeBase64/1, decodeBase64/1, encodeBase64Url/1, decodeBase64Url/1,
     to_hex/1,parse_term/1, dict_find/3]).
@@ -55,9 +55,6 @@ terminate_linked(Reason) ->
     ok.
 
 
-new_uuid() ->
-    list_to_binary(to_hex(crypto:rand_bytes(16))).
-
 to_hex([]) ->
     [];
 to_hex(Bin) when is_binary(Bin) ->
@@ -394,4 +391,4 @@ url_encode([H|T]) ->
         end
     end;
 url_encode([]) ->
-    [].
\ No newline at end of file
+    [].