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2 commits

Author SHA1 Message Date
unknown
3c97d24f74 MDEV-4984: Implement MASTER_GTID_WAIT() and @@LAST_GTID.
Couple of small fixes following buildbot testing.
2014-02-08 01:16:45 +01:00
unknown
4e6606acad MDEV-4984: Implement MASTER_GTID_WAIT() and @@LAST_GTID.
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).
2014-02-07 19:15:28 +01:00