Cleanup of slave code:

- Added testing if connection is killed to shortcut reading of connection data
  This will allow us later in 10.2 to do a cleaner shutdown of slaves (less errors in the log)
- Add new status variables: Slaves_connected, Slaves_running and Slave_connections.
- Use MYSQL_SLAVE_NOT_RUN instead of 0 with slave_running.
- Don't print obvious extra warnings to the error log when slave is shut down normally.

1 files changed, 9 insertions, 7 deletions

diff --git a/sql/rpl_mi.cc b/sql/rpl_mi.cc
index ae6cc1ac0a2..a7ee3f3f45e 100644
--- a/sql/rpl_mi.cc
+++ b/sql/rpl_mi.cc
@@ -35,7 +35,8 @@ Master_info::Master_info(LEX_STRING *connection_name_arg,
    rli(is_slave_recovery), port(MYSQL_PORT),
    checksum_alg_before_fd(BINLOG_CHECKSUM_ALG_UNDEF),
    connect_retry(DEFAULT_CONNECT_RETRY), inited(0), abort_slave(0),
-   slave_running(0), slave_run_id(0), clock_diff_with_master(0),
+   slave_running(MYSQL_SLAVE_NOT_RUN), slave_run_id(0),
+   clock_diff_with_master(0),
    sync_counter(0), heartbeat_period(0), received_heartbeats(0),
    master_id(0), prev_master_id(0),
    using_gtid(USE_GTID_NO), events_queued_since_last_gtid(0),
@@ -1273,23 +1274,24 @@ bool Master_info_index::give_error_if_slave_running()
    The LOCK_active_mi must be held while calling this function.
 
    @return
-   TRUE  	If some slave SQL thread is running.
-   FALSE	No slave SQL thread is running
+   0            No Slave SQL thread is running
+   #		Number of slave SQL thread running
 */
 
-bool Master_info_index::any_slave_sql_running()
+uint Master_info_index::any_slave_sql_running()
 {
+  uint count= 0;
   DBUG_ENTER("any_slave_sql_running");
   if (!this) // master_info_index is set to NULL on server shutdown
-    DBUG_RETURN(TRUE);
+    DBUG_RETURN(count);
 
   for (uint i= 0; i< master_info_hash.records; ++i)
   {
     Master_info *mi= (Master_info *)my_hash_element(&master_info_hash, i);
     if (mi->rli.slave_running != MYSQL_SLAVE_NOT_RUN)
-      DBUG_RETURN(TRUE);
+      count++;
   }
-  DBUG_RETURN(FALSE);
+  DBUG_RETURN(count);
 }