Jeff,
> Is that an OS-dependent parameter? I always assumed it depended entirely
> on hardware. I have no way to test it for myself though, so I just leave
> full_page_writes=on to be safe.
It's a question of whether your HW+OS can guarentee no torn page writes for
the xlog. Running on Sun hardware combined with Solaris 10 with the xlog
mounted forcedirectio, the Solaris folks are convinced we are torn-page-proof
and so far we haven't been able to prove them wrong. And, on Solaris it's a
substantial performance gain (like, 8-10% on OLTP benchmarks).
--
Josh Berkus
PostgreSQL @ Sun
San Francisco