Re: more anti-postgresql FUD

On Fri, 2006-10-13 at 13:52 -0400, Merlin Moncure wrote:
> On 10/13/06, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Martijn van Oosterhout <kleptog(at)svana(dot)org> writes:
> > > Is that really true? In theory block n+1 could be half a revolution
> > > after block n, allowing you to commit two transactions per revolution.
> >
> > Not relevant, unless the prior transaction happened to end exactly at a
>
> does full page writes setting affect this?
>

No, full page writes only affects checkpoints.

For a transaction to commit, some bits must hit permanent storage
*somewhere*. If that location is in one general area on disk, you must
either commit several transactions at once (see commit_delay), or you
must wait until the next revolution to get back to that area of the
disk.

Regards,
Jeff Davis