From 9237801d22a38d2643ffe94ab626c4d2815012dd Mon Sep 17 00:00:00 2001 From: Dan Gudmundsson Date: Thu, 10 Oct 2013 10:55:46 +0200 Subject: mnesia: Synchronize lock cleanup after mnesia down Bad timing could lead to hanging transactions after a mnesia down from a node with sticky locks. Excellent bug report from janchochol Situation: * node A and B have copies of table T * node A ows sticky of table T * node A goes down (e.g. crash) * node B tries to perform transactional operation on table T (e.g. mnesia:select) In this situation there is possibility that first (and maybe other) transaction on node B will hang indefinitely. This is caused by race condition, when transaction process send lock request operation to node A and waits for reply. When node A is down it will never send reply, so process on node B will be stuck forever. Reason is that message sent to mnesia_locker gen_server from mnesia_locker:mnesia_down can be received after mnesia_locker gen_server already replies to transaction processes with {switch, N, Req} and node N is down. Monitoring remote process when sending request to other node should be safe solution. --- lib/mnesia/src/mnesia.appup.src | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) (limited to 'lib/mnesia/src/mnesia.appup.src') diff --git a/lib/mnesia/src/mnesia.appup.src b/lib/mnesia/src/mnesia.appup.src index 355aafb215..c245299740 100644 --- a/lib/mnesia/src/mnesia.appup.src +++ b/lib/mnesia/src/mnesia.appup.src @@ -1,22 +1,16 @@ %% -*- erlang -*- {"%VSN%", [ - {"4.7.1", [{restart_application, mnesia}]}, - {"4.7", [{restart_application, mnesia}]}, - {"4.6", [{restart_application, mnesia}]}, - {"4.5.1", [{restart_application, mnesia}]}, - {"4.5", [{restart_application, mnesia}]}, + {<<"4\\.1[0-9].*">>, [{restart_application, mnesia}]}, + {<<"4\\.[5-9].*">>, [{restart_application, mnesia}]}, {"4.4.19", [{restart_application, mnesia}]}, {"4.4.18", [{restart_application, mnesia}]}, {"4.4.17", [{restart_application, mnesia}]}, {"4.4.16", [{restart_application, mnesia}]} ], [ - {"4.7.1", [{restart_application, mnesia}]}, - {"4.7", [{restart_application, mnesia}]}, - {"4.6", [{restart_application, mnesia}]}, - {"4.5.1", [{restart_application, mnesia}]}, - {"4.5", [{restart_application, mnesia}]}, + {<<"4\\.1[0-9].*">>, [{restart_application, mnesia}]}, + {<<"4\\.[5-9].*">>, [{restart_application, mnesia}]}, {"4.4.19", [{restart_application, mnesia}]}, {"4.4.18", [{restart_application, mnesia}]}, {"4.4.17", [{restart_application, mnesia}]}, -- cgit v1.2.3