Re: Advantage of Raw Device-based database over Filesystem-based Database (Is there any?)

From: John P. Higgins <jh33378_at_deere.com>
Date: Wed, 02 Sep 1998 22:07:37 -0500
Message-ID: <35EE07F8.2BA148A9@deere.com>

I don't believe this.

When I used file systems, I would:
    use lvcreate to create a 1-2GB logical volume
    mount a file system on that logical volume
    create (or extend) a tablespace with a file that consumed the entire file system
Of course, unix consumed part of the file system for file system inodes.

With raw, I:
    use lvcreate to create a 1-2GB logical volume.
    create (or extend) a tablespace with a file size that consumed the entire logical volume. Since there is no file system, no disk is wasted on inodes.

Backup and recovery are basically the same:
    for every tablespace
        ALTER TABLESPACE ____ BEGIN BACKUP;
        for each file / raw device in the tablespace
            tar the file or dd the raw device
        ALTER TABLESPACE ____ END BACKUP;

The unix dd command is not rocket science (I can do it). It is just not tar or cp.

Susan wrote:

Oracle themselves don't have a good answer, you may get some nominal
performance increase from raw devices.  Unless the application and
environment are such that squeezing every bit of performance out of it
is necessary, then I'd advise you to use "cooked" filesystems.  From a
DBAs perspective, they are much easier to administer and manage.

- sooz

On Tue, 01 Sep 1998 16:48:20 -0700, "giau45@yahoo.com"
<giau45@yahoo.com> wrote:

>Is there any advantage of Raw Device-Based Database over
>Filesystem-Based Database ?
>
>In what case, one prefers Raw Device-Based database over
>Filesystem-Based database ?
>
>Thanks
>

  Received on Wed Sep 02 1998 - 22:07:37 CDT