> Andrei Elkin <andrei.el...@pp.inet.fi> writes: > >> And really why not >> >> 3. SET @@GLOBAL.gtid_binlog_state=list-without-d; > > The main issue I see with this if the master is actively adding new > transactions (in other domains than d). It will be hard for the user > to know > the right value to set without doing something like FLUSH TABLES WITH > READ > LOCK during the operation to stop transactions between selecting > @@global.gtid_binlog_state and SETting the new value. > > Whereas FLUSH BINARY LOGS DELETE DOMAIN d only needs a shorter-lived > lock on > the binlog while doing the rotation and check.
Right. > > Other than that, I agree SET gtid_binlog_state could be a good fit. Then a function to discard a domain term would do: SET @@gtid_binlog_state=gtid_discard_domain(@@gtid_binlog_state,'d') While this time it would be new object introduced still it's of var setting semantics and might be generally useful too. How about it? Andrei > >> the new state value must cover (include as a math set) all gtids >> in >> the current list of binlog files. (Naturally I consider [presume] >> Gtid_list >> header of a binlog file assumes there are no gaps or out-of-order >> in the preceding files. That is it provides the right-hand-side of >> gtid seqno range for each domain-server pair). > > Yes. (There is no strict requirement of no gaps in MariaDB GTID, but > it > should not matter here). > >> So we conduct the 1-3 procedure. Pseudo-sql would go like >> >> mysql> /* 1. */ SELECT @@global.gtid_binlog_state into >> mysql> @pre_purge_state; >> mysql> /* 2. */ PURGE LOGS to 'b.2' >> mysql> /* 3. */ SET >> mysql> @@global.gtid_binlog_state="REPLACE"(@pre_purge_state, >> mysql> '0-1-1', ''); > > So this requires that there are no new transactions written to binlog > between (1) and (3). > >> The check technically is a comparison between Gtid_list.d term in >> the oldest file and @pre_purge_state.d one. >> If they are equal the current binlog files are proven not to contain >> events from 'd'. > > Agree. > > - Kristian. > _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : maria-developers@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
