Re: Disable page writes when fsync off, add GUC

Peter Eisentraut wrote:
> Bruce Momjian wrote:
> > This patch disables page writes to WAL when fsync is off, because
> > with no fsync guarantee, the page write recovery isn't useful.
> >
> > This also adds a full_page_writes GUC to turn off page writes to WAL.
> > Some people might not want full_page_writes, but still might want
> > fsync.
>
> Do you have some numbers to suggest that there is a performance benefit
> to be had?

Josh reported page writes to be a big hit (which we already knew), but I
don't have any with fsync off, though it seems like a no-brainer.
However, I am thinking decoupling them is best.

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