On Mon, 2009-12-21 at 10:38 -0500, Tom Lane wrote: > Alvaro Herrera <alvhe...@commandprompt.com> writes: > > Andres Freund wrote: > >> The logic behind this seems fine except in the case of dropping a > >> database. > >> There you very well might have a open connection without an open snapshot. > > > Perhaps the simplest fix is to ensure that drop database gets a snapshot? > > I confess to not having followed the thread closely, but why is DROP > DATABASE special in this regard? Wouldn't we soon find ourselves > needing every utility command to take a snapshot?
Andres has worded this a little imprecisely, causing a confusion. In cases regarding HS we need to be clear whether the interacting sessions are on the master or on the standby to understand the reasons for poor interactions. What he means is that you can be connected to the standby without an open snapshot (from the standby) at the point we replay a drop database command that had been run on the master. That case currently causes the bug, created by my recent change to GetConflictingVirtualXids(). Giving the drop database a snapshot is not the answer. I expect Andres to be able to fix this with a simple patch that would not effect the case of normal running. -- Simon Riggs www.2ndQuadrant.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
