Re: Raw Logical Volumes vs. Unix File Systems

In article <CunMG5.53u_at_shellgate.shell.com>, Stephen Pace <pace_at_shell.com> wrote:
>I need some information about creating Oracle databases on Raw Logical
>Volumes vs. standard Unix file systems.
>What are the advantages? Are they that much faster? We have a 6-8 GB
>Oracle 7 database sitting on an RS/6000 590, and we are starting to see

The Book (Oracle7 Administrator's reference guid) says a performance improvement of 10-15% is a reasonable expectation, since you are not going thru the AIX kernel buffers and the filesystem on the way to the disk. When we were installing on my most recent HP, the guy from Oracle Core Technologies, indicated his experience was more like 5-7%.

I had 130 installations of Oracle on AIX (3.2.2) and we elected to go with regular filesystems because:
- backup and restore was much more robust and flexible - using LVM, we could tune the placement of the datafiles on the disks,   as well as actual placement on the individual disks (center vs. edge) - we had the option of striping and mirroring at the LVM level as a   performance option when we grew the DB large enough or management   decided the system was critical enough for mirroring. - performance differential not large enough to compensate for extra   hassle.

Hope that is of some use as you decide.
Regards,

--
Lynn Osburn   losburn_at_omcssi.com
Reverse Depravity!