Compression
Mladen Gogala
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:
http://www.oracle.com/technology/products/database/compression/
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.
Mladen Gogala
This is an April's fool joke:
SQL> set serveroutput on
SQL> exec dbms_comp_advisor.getratio('NEWS','NEWS_PROGRAMS','OLTP',10);
Invalid Compression option for the current COMPAT setting
PL/SQL procedure successfully completed.
SQL> show parameter compat
NAME TYPE VALUE
------------------------------------ -----------
------------------------------
compatible string 10.2.0.4
plsql_v2_compatibility boolean FALSE
SQL> SQL> select * from v$version;
BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Prod
PL/SQL Release 10.2.0.4.0 - Production
CORE 10.2.0.4.0 Production
TNS for Linux: Version 10.2.0.4.0 - Production
NLSRTL Version 10.2.0.4.0 - Production
This doesn't give me anything. This is funny, to have my database vendor
joking with me. I wonder what else there might be a joke?
hpuxrac
snip
> 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:
>
> http://www.oracle.com/technology/products/database/compression/
> 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?
This is covered in the concepts and new features guides for 11g.
Mladen Gogala
John, I know this is covered, but the package in question looks like it
could give us something on the Oracle 10g. It doesn't. It's an April fool
joke. My question wasn't about the Oracle 11g, I know about "COMPRESS FOR
ALL OPERATIONS in 11.1 and COMPRESS FOR OLTP in Oracle 11.2. You need an
advanced compression license to do that. The URL I pointed you to explains
the package that is supposed to run even on Oracle 9i. The page does not
explain that the package doesn't really give you anything, that it only
provides another interface to the compression that is already in the
kernel. The information on that page is definitely misleading.
gazzag
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.
-g
joel garry
Or, cpu queues could lengthen, slowing down latch processing, slowing
down SGA operations, slowing down I/O requests, increasing cpu
queues...
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?
jg
--
@home.com is bogus.
http://www.signonsandiego.com/news/2009/dec/15/makeover-family-trying-stave-foreclosure/