Re: pgsql-server: Add: > > * Allow buffered WAL writes

Tom Lane wrote:
> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > Tom Lane wrote:
> >> Who exactly signed onto this as a good idea? It sure doesn't square
> >> with my ideas of an ACID database. Committed means committed, not
> >> "maybe if you're lucky committed".
>
> > True but we support fsync. Certainly it would be more useful than
> > fsync, and it might allow us to remove fsync.
>
> How so? fsync off is for I-don't-care-about-this-data-at-all cases
> (primarily development, though loading already-archived data can
> qualify too). I'm not seeing a use-case for "I care about this data,
> but only once it's more than N seconds old". It certainly does not
> replace "just go as fast as you can", which is what fsync off means.
>
> > No one has to sign TODO items, BTW. They are added and removed as
> > requested.
>
> [ shrug... ] So if I request removal of this item, it will go away
> again? It hasn't reached the age needed to guarantee commit ;-)

Many databases offer this feature. The submitter asked for it, and I
think it is a good idea. For cases where you are running an in-house
app, you can tell your employees to re-key the stuff they did just
before the crash. It doesn't work for web apps and stuff, but for
smaller cases it is fine.

With Informix, the logic used by most customers I dealt with was that
unbuffered logging was too slow and they were willing to do a few rekeys
for the performance gain.

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