> > > Darren, can you clarify this? Why does it send that message? How does > it allow commits not to wait for ordered writesets? >
There are two channels. One for total order writesets (changes to the DB). The other is simple order for aborts, commits, joins (systems joining the replica), etc. The simple channel is necessary, because we don't want to wait for total ordered changes to get an abort message and so forth. In some cases you might get an abort or a commit message before you get the writeset it refers to. Lets say we have systems A, B and C. Each one has some changes and sends a writeset to the group communication system (GSC). The total order dictates WS(A), WS(B), and WS(C) and the writes sets are recieved in that order at each system. Now C gets WS(A) no conflict, gets WS(B) no conflict, and receives WS(C). Now C can commit WS(C) even before the commit messages C(A) or C(B), because there is no conflict. Hope that helps, Darren ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
