[couchdb] branch fix-couch-server-avoid-lru-copy-3.0.x created (now fce6c78)

[va...@apache.org]

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vatamane pushed a change to branch fix-couch-server-avoid-lru-copy-3.0.x
in repository https://gitbox.apache.org/repos/asf/couchdb.git.


      at fce6c78  Do not copy the #server.lru field to async openers

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     new fce6c78  Do not copy the #server.lru field to async openers

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[couchdb] 01/01: Do not copy the #server.lru field to async openers

[va...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

vatamane pushed a commit to branch fix-couch-server-avoid-lru-copy-3.0.x
in repository https://gitbox.apache.org/repos/asf/couchdb.git

commit fce6c782e63b6d772c1dccd50f41df13b828e044
Author: Paul J. Davis <pa...@gmail.com>
AuthorDate: Tue Mar 31 16:25:38 2020 -0500

    Do not copy the #server.lru field to async openers
    
    This copy slowed down the `erlang:spawn_link/3` call considerably.
    Measurements in the wild showed the cost of that `spawn_link/3` going
    from roughly 8 uS to 800 uS.
---
 src/couch/src/couch_server.erl | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/couch/src/couch_server.erl b/src/couch/src/couch_server.erl
index 909e238..b2f8fde 100644
--- a/src/couch/src/couch_server.erl
+++ b/src/couch/src/couch_server.erl
@@ -381,10 +381,13 @@ maybe_close_lru_db(#server{lru=Lru}=Server) ->
     end.
 
 open_async(Server, From, DbName, Options) ->
+    NoLRUServer = Server#server{
+        lru = redacted
+    },
     Parent = self(),
     T0 = os:timestamp(),
     Opener = spawn_link(fun() ->
-        Res = open_async_int(Server, DbName, Options),
+        Res = open_async_int(NoLRUServer, DbName, Options),
         IsSuccess = case Res of
             {ok, _} -> true;
             _ -> false