On Fri, May 1, 2009 at 7:19 AM, Alex Esterkin <[email protected]> wrote: > I have several architectural comments. > > Use GUIDs > > Session ID collisions may cause all sorts of problems. Perhaps, it makes > sense to use globally unique identifiers? GUIDs are 16 bytes long. > > Global TransactionId (either global scope or transaction domain scope) > > Global transaction id implies that there is a global transaction manager > somewhere capable of committing or aborting distributed global > transactions. Thus, global transaction IDs have to be generated by such > global transaction manager or registered with it and have a meaning only in > the context of such global transaction manager. As transactions can be > nested, it may make sense to consider nesting global transaction managers. > What may be transaction manager discovery mechanism and how do you encode > all this information in global transaction IDs?
In the context of MySQL replication this has nothing to do with distributed transactions. It (global transaction ID) means there is a monotonically increasing counter maintained by the master, included in binlog events and preserved across master failover. See http://code.google.com/p/google-mysql-tools/wiki/GlobalTransactionIds This gets more complicated with multi-master replication and if you try to replicate multiple masters into one slave. -- Mark Callaghan [email protected] _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
