Replication:

Now the I/O thread (in flush_master_info()) flushes the relay log to disk
after reading every event. Slower but provides additionnal safety in case
of brutal crash.
I had to make the flush optional (i.e. add a if(some_bool_argument) in the function)
because sometimes flush_master_info() is called when there is no usable
relay log (the relay log's IO_CACHE is not initialized so can't be flushed).

1 files changed, 5 insertions, 2 deletions

diff --git a/sql/sql_repl.cc b/sql/sql_repl.cc
index c30409fd0cb..3c477afa300 100644
--- a/sql/sql_repl.cc
+++ b/sql/sql_repl.cc
@@ -1085,8 +1085,11 @@ int change_master(THD* thd, MASTER_INFO* mi)
      strmake(mi->master_log_name, mi->rli.group_master_log_name,
              sizeof(mi->master_log_name)-1);
   }
-
-  flush_master_info(mi);
+  /*
+    Relay log's IO_CACHE may not be inited, if rli->inited==0 (server was never
+    a slave before).
+  */
+  flush_master_info(mi, 0);
   if (need_relay_log_purge)
   {
     relay_log_purge= 1;