Re: First steps with 8.3 and autovacuum launcher

Tom Lane escribió:
> I wrote:
> > Actually, if you wanted a low-hanging solution to that, it would
> > probably be to revert this 8.2 patch:
> > http://archives.postgresql.org/pgsql-committers/2006-09/msg00284.php
>
> Uh ... never mind, that won't help at all. Reducing the lock taken for
> ANALYZE could allow CREATE INDEX (ShareLock) to run concurrently. But
> ALTER TABLE wants AccessExclusive lock, and no amount of fine-tuning of
> the conflicting lock will help.
>
> 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?

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Alvaro Herrera http://www.CommandPrompt.com/
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