Re: [GENERAL] Vacuum and Transactions

> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> >> In 7.2, VACUUM will not require an exclusive lock.
>
> > Care to elaborate on that? How are you going to do it?
>
> Uh, have you not been paying attention to pg-hackers for the
> last two months?
>
> I am assuming here that concurrent VACUUM will become the default
> kind of vacuum, and the old style will be invoked by some other
> syntax (VACUUM FULL ..., maybe).

OK, I just talked to Tom on the phone and here is his idea for 7.2. He
says he already posted this, but I missed it.

His idea is that in 7.2 VACUUM will only move rows within pages. It
will also store unused space locations into shared memory to be used by
backends needing to add rows to tables. Actual disk space compaction
will be performed by new a VACUUM FULL(?) command.

The default VACUUM will not lock the table but only prevent the table
from being dropped.

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