Chris,
> Remounting the fs where $PGDATA lives with "forcedirectio"
> (together with logging, that is default) did not help
> (if not harm...) performance.
Not all of PG. JUST pg_xlog. forcedirectio is only a good idea for the xlog.
> Quickly playing around with wal_buffers on Linux and Mac OS X
> I see it influences the performance of my test a bit, maybe in the
> 10-20% range (I'm really doing quick tests, nothing systematic),
> but nowhere near as spectacularly as on Solaris.
>
> I'm happy so far, but I find it very surprising that this single
> parameter has such an impact (only on) Solaris 10.
That *is* interesting. I hadn't tested this previously specifically on
Solaris.
--
Josh Berkus
Aglio Database Solutions
San Francisco