I'd really like to see us find a way to apply some version of this
> patch. I was in favor of the concept 3 years ago when we did this the
> first time, and I've subsequently done quite a bit of work (viz., MVCC
> catalog snapshots) to eliminate the main objection that was raised at
> that time. But it's really hard to reason about what might happen
> with lowered lock levels, and convince yourself that there's
> absolutely nothing that can ever go wrong. I don't know what to do
> about that tension, but I think even modest improvements in this area
> stand to benefit an awful lot of users.
Wouldnt MVCC's strictness rules pose harder restrictions on pg_dump instead
of relaxing them?