Re: The results of my PostgreSQL/filesystem performance tests

> I'm likely going to make this the default for PostgreSQL on FreeBSD
> starting with 7.4 (just posted something to -hackers about this)f.  If
> you'd like to do this in your testing, just apply the following patch.
>
> Right now PostgreSQL defaults to 8K blocks, but FreeBSD uses 16K
> blocks which means that currently, reading two blocks of data in PG is
> two read calls to the OS, one reads 16K of data off disk and returns
> the 1st page, the 2nd call pulls the 2nd block from the FS cache.  In
> making things 16K, it avoids the need for the 2nd system call which is
> where the performance difference is coming from, afaikt.  -sc

Are you _sure_ this won't cause any atomicity problems?  Can FreeBSD write
16k as an atomic unit?

Chris