Alvaro Herrera <alvherre@commandprompt.com> writes:
> Tom Lane escribi�:
>> It might be possible to solve this if we reduce the strength of the lock
>> used for ALTER TABLE. We'd have to go through all the commands
>> potentially issued by a pg_dump script and see if they could all be made
>> to run concurrently with autovac, which is a bit nervous-making but
>> might be feasible; and I'm afraid tablecmds.c would need some
>> restructuring to not use the same lock type for every variant of ALTER.
>> But it seems like a path worth investigating.
> Right. Are you going to work on it, or do you want me to propose a
> patch?
If you have time to work on it, please do. But it seems like you first
need to do some investigation --- the idea may not work at all.
In any case, this would still only fix things for pg_restore, and I
remain concerned that people will gripe about autovacuum blocking
locks. The idea of kicking autovac off tables remains probably more
interesting in the long run.
regards, tom lane