• unknown's avatar
    MDEV-4984: Implement MASTER_GTID_WAIT() and @@LAST_GTID. · 4e6606ac
    unknown authored
    MASTER_GTID_WAIT() is similar to MASTER_POS_WAIT(), but works with a
    GTID position rather than an old-style filename/offset.
    
    @@LAST_GTID gives the GTID assigned to the last transaction written
    into the binlog.
    
    Together, the two can be used by applications to obtain the GTID of
    an update on the master, and then do a MASTER_GTID_WAIT() for that
    position on any read slave where it is important to get results that
    are caught up with the master at least to the point of the update.
    
    The implementation of MASTER_GTID_WAIT() is implemented in a way
    that tries to minimise the performance impact on the SQL threads,
    even in the presense of many waiters on single GTID positions (as
    from @@LAST_GTID).
    4e6606ac
queues.h 3.54 KB