Re: FreeBSD Softupdates??

* Alfred Perlstein <bright(at)wintelcom(dot)net> [000926 08:42] wrote:
> * Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> [000926 07:12] wrote:
> > -- Start of PGP signed section.
> > > On Tue, Sep 26, 2000 at 03:20:31AM -0700, Alfred Perlstein wrote:
> > > > It can cause problems because softupdates makes meta data changes
> > > > (in this case file creation/removal) asyncronously, the same actually
> > > > happens with most other logging filesystems that don't support
> > > > transactions.
> > >
> > > I've been running FreeBSD 4.1 with soft updates on my development box
> > > for a while now without any problems at all. Although it's not
> > > production so there's not a lot of load on PgSQL.
> > >
> > > I don't know if it hurts or hampers performance.
> >
> > Good question. I can see soft updates improving performance because it
> > flushes meta-data writes all at once, rather than each time a file is
> > created/destroyed. I don't see any downside for PostgreSQL. The
> > default fsync() will still work, or at least it should. This is not the
> > same as mounting a volume as async.
>
> You are correct, softupdates will honour a fsync and stabilize the
> file (make sure it's a round if you have a crash).

UFS doesn't support 'round' files, I meant 'around' of course. :)

--
-Alfred Perlstein - [bright(at)wintelcom(dot)net|alfred(at)freebsd(dot)org]
"I have the heart of a child; I keep it in a jar on my desk."