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, 6 insertions, 1 deletions

diff --git a/sql/repl_failsafe.cc b/sql/repl_failsafe.cc
index 0d2da91e015..084f7386b7b 100644
--- a/sql/repl_failsafe.cc
+++ b/sql/repl_failsafe.cc
@@ -908,7 +908,12 @@ int load_master_data(THD* thd)
 	// don't hit the magic number
 	if (active_mi->master_log_pos < BIN_LOG_HEADER_SIZE)
 	  active_mi->master_log_pos = BIN_LOG_HEADER_SIZE;
-	flush_master_info(active_mi);
+        /*
+          Relay log's IO_CACHE may not be inited (even if we are sure that some
+          host was specified; there could have been a problem when replication
+          started, which led to relay log's IO_CACHE to not be inited.
+        */
+	flush_master_info(active_mi, 0);
       }
       mysql_free_result(master_status_res);
     }