Re: Harddisk performance degrading over time?

> On Sun, 24 Jun 2001, Bruce Momjian wrote:
>
> > > Oh yeah,
> > > vacuuming is not the problem here.
> > >
> > > Thanks anyway... :)
> > >
> > > And also, it seems that it is the indexed searches that is suffering the
> > > most. The non-indexed searches is less affected. This is not only PostgreSQL
> > > but also MySQL.
> >
> > I know the BSD filesystems are self-defragmenting.  I don't know if the
> > ext2 filesystems are the same.  Surely someone must know.
> Not exactly, BSD ffs (fast filesystem) isn't self-defragmenting, it just
> fragments differently [less than] ext2 :)

Yes, BSD is more "doesn't fragment much" rather than "self
defragmenting".

> See this for paper and some tools to get ffs fragmentation stats:
> http://www.eecs.harvard.edu/~margo/usenix.195
> (it has links to critique of the paper as well)
>
> There's a tool ftp://ftp.uk.linux.org/pub/linux/sct/defrag/ to defrag ext2
> filesystem, but its considered to be alpha quality and not really
> maintained.

Yes, thanks for the clarification.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026