On 2014-04-28 13:58:10 -0400, Tom Lane wrote: > Claudio Freire <klaussfre...@gmail.com> writes: > > On Mon, Apr 28, 2014 at 12:52 PM, Alvaro Herrera > > <alvhe...@2ndquadrant.com> wrote: > >> Tom Lane wrote: > >>> Abhijit Menon-Sen <a...@2ndquadrant.com> writes: > >>>> In the past, we've had situations where "everything is hung" turned out > >>>> to be because of a script that ran manual VACUUM that was holding some > >>>> lock. It's admittedly not a huge problem, but it might be useful if a > >>>> manual VACUUM could be cancelled the way autovacuum can be. > > >>> I think the real answer to that is "stop using manual VACUUM". > > >> As much as I'm a fan of autovacuum, that's not always possible. > > > Or even recommended, unless the docs changed radically in the last > > couple of weeks. > > Actually, having just looked at the code in question, I think this whole > thread is based on an obsolete assumption. AFAICS, since commit b19e4250b > manual vacuum behaves exactly like autovacuum as far as getting kicked off > the exclusive lock is concerned. There's certainly not any tests for > autovacuum in lazy_truncate_heap() today.
I don't think this is about the truncation thing, but about the deadlock.c/proc.c logic around DS_BLOCKED_BY_AUTOVACUUM. I.e. that a autovacuum is cancelled if user code tries to acquire a conflicting lock. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
