On Mon, Jan 12, 2009 at 2:05 PM, Heikki Linnakangas <heikki.linnakan...@enterprisedb.com> wrote: > Well, I've been keeping an eye on both Hot Standby and Synchronous > Replication patches. IMHO the Hot Standby patch is architecturally sound, > and while I suggested some pretty big changes just recently (which Simon > picked up and did already), it's in pretty good shape. No doubt there's > still some issues that haven't been uncovered, comments to be fixed, > documentation to be written, but no showstoppers or anything that requires a > major rewrite. There's one todo item left: prepared transactions, but I > don't think there's anything fundamentally hard about them, just needs to be > fixed. Simon mentioned usability issues related to who/when queries get > cancelled, but I think we've discussed that to death already and the patch > handles it quite nicely.
Cool - that's good to hear. > IMHO, the synchronous replication isn't in such good shape, I'm afraid. I've > said this before, but I'm not happy with the "built from spare parts" nature > of it. You shouldn't have to configure an archive, file-based log shipping > using rsync or whatever, and pg_standby. All that is in addition to the > direct connection between master and slave. The slave really should be able > to just connect to the master, and download all the WAL it needs directly. > That's a huge usability issue if left as is, but requires very large > architectural changes to fix. Yeah, I wasn't thinking about this, but you had mentioned it before, and I thought (and think) it's a pretty fair criticism. I think the base backup should be integrated into the mechanism as well. I want to just be able to configure the master and slave for replication, fire up the slave, and walk away. Without that, I agree that it's likely to be too cumbersome for any actual use. >> One thing I find interesting is that the "Infrastructure Changes for >> Recovery" patch became the foundation for both "Hot Standby" and >> "Synchronous Replication". That implies that those changes might be >> of somewhat more general interest, at least as the foundation for >> further work. If we HS and/or SR are out of reach, it might be worth >> at least looking to see if any of that infrastructure work can be >> reasonably be committed for 8.4. > > Yeah, being able to do an online checkpoint after recovery has some value of > its own. Is there anything standing in the way of committing that patch? I don't think I've seen anything mentioned on -hackers. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers