On Fri, May 29, 2015 at 3:09 PM, Magnus Hagander <magnus@hagander.net> wrote:
> Do you have any feeling of how likely people are to actually hit the
> multixact one? I've followed some of that impressive debugging you guys did,
> and I know it's a pretty critical bug if you hit it, but how wide-spread
> will it be?
That precise problem has been reported a few times, but it may not be
widespread. I don't know. My bigger concern is that, at present,
taking a base backup is broken. I haven't figured out the exact
reproduction scenario, but I think it's something like this:
- begin base backup
- checkpoint happens, truncating pg_multixact
- at this point pg_multixact gets copied
- end base backup
I think what will happen on replay is that replaying the checkpoint,
it will try to reference pg_multixact files that don't exist any more
and die with a fatal error.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
