asynchronous_commit=off is a doubt for responsive environment (pg manual). for ex.
a game player , has to perform next move on basis of his/her previous move plus other players move.
all is sent to table and for each player a particular set is retrieved with a minimalistic data portfolio
> Date: Thu, 18 Oct 2012 11:24:00 -0300
> From: alvherre@2ndquadrant.com
> To: laurenz.albe@wien.gv.at
> CC: arvindps@hotmail.com; pgsql-general@postgresql.org
> Subject: Re: [GENERAL] Improve MMO Game Performance
>
> Albe Laurenz wrote:
> > Arvind Singh wrote:
> > > Are there any particular settings or methods available to improve Just
> > insert_table operations
> >
> > The obvious ones:
> > - Wrap several of them in a transaction.
> > - Increase checkpoint_segments.
> > - Set fsync=off and hope you don't crash.
>
> I think it would work to set asynchronous_commit=off for the
> transactions that insert moves. That way, the fsync flushes happen in
> the background and are batched. Raising wal_buffers is probably a good
> idea, and keep an eye on how the walwriter is doing.
>
> --
> Álvaro Herrera http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Training & Services