From: joel garry on 15 Dec 2009 11:43
On Dec 15, 2:13 am, gazzag <gar...(a)jamms.org> wrote:
> On 14 Dec, 19:41, Mladen Gogala <n...(a)email.here.invalid> wrote:
> > The word "compression" is very fashionable these days. I find that
> > strange because everybody keeps telling me how cheap disks are these days
> > and yet, there is a slew of compression algorithms all around: MP3,
> > MPEG-2,OGG, ZIP, BZIP2, GZIP, everything is compressed to save the
> > inexpensive and cheap disk space. Oracle seems to have noticed the
> > fashion so they have released a package which should produce the 11.2
> > behavior. The package is called "Oracle Advanced Compression Advisor" and
> > is described here:
> > compression-advisor.html
> > Has anybody played with that? Is there any possibility of compressing the
> > table for OLTP or ("ALL OPERATIONS" in 11.1) in Oracle 10g?
> > I thought of compressing this message to make it more in and fashionable,
> > but the unfortunate effect would be that the message would be somewhat
> > less readable. This message will, however, self-destruct in 5 minutes
> > after reading.
> > --http://mgogala.byethost5.com
> I don't believe that compression is simply about saving "cheap" disk
> space as it used to be. Now that CPUs are so much more powerful, data
> can be uncompressed very quickly in memory reducing disk I/O.
Or, cpu queues could lengthen, slowing down latch processing, slowing
down SGA operations, slowing down I/O requests, increasing cpu
On my machine, there are a few misbehaving reports that are known to
peg a cpu (sometimes thrashing SGA, sometimes in-app memory
thrashing). When there is just one, not really a problem. When there
are several, sometimes a problem. I wouldn't want to add more cpu
load when there is a problem, that would make a real problem. The
root problem is management wanting up to the minute DSS reports on an
OLTP system. Any db is going to have to deal with that. Isn't the
direction of Oracle to put everything into a big db for all purposes?
@home.com is bogus.