Re: COPY LOCK for WAL bypass - Mailing list pgsql-patches

From Bruce Momjian
Subject Re: COPY LOCK for WAL bypass
Date
Msg-id 200512211317.jBLDHkt03827@candle.pha.pa.us
Whole thread Raw
In response to Re: COPY LOCK for WAL bypass  (Simon Riggs <simon@2ndquadrant.com>)
List pgsql-patches
Simon Riggs wrote:
> On Sun, 2005-12-18 at 22:03 -0500, Chris Browne wrote:
> > simon@2ndquadrant.com (Simon Riggs) writes:
> > > On Sat, 2005-12-10 at 12:07 +0000, Simon Riggs wrote:
> > >> Following patch implements COPY ... FROM ... LOCK
> > >
> > > Patch now updated so that it includes an additional optimization of
> > > COPY, so that WAL will not be written in the transaction that created
> > > the table.
> > >
> > > This now gives two fast paths for COPY:
> > > 1) COPY LOCK
> > > 2) COPY in same transaction (e.g. reloading a pg_dump)
> >
> > I presume that if this doesn't go into WAL, that means that this kind
> > of update wouldn't play with PITR, right?
>
> You're right.
>
> PITR is designed for normal production use, rather than initial loading.
> It is also fairly common to turn PITR off permanently in larger data
> warehouses, which is also where these optimizations are aimed.
>
> I'll take the hint and write the docs then. :-)

I assume in addition to a documentation mention, you will disable this
feature when PITR is on, right?  (Rather than just document something
that is unsafe, we disable it.)

--
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