Re: Unix File System vs. Raw Devices

From: Steve Phelan <stevep_at_XXnospamXX.toneline.demon.co.uk>
Date: Thu, 7 May 1998 16:03:35 +0100
Message-ID: <894553399.2498.0.nnrp-04.c2de712e@news.demon.co.uk>

See below:

>Phil Hoggins wrote in message <01bd78ba$b186e5e0$d875549e_at_w-philh>...
>My advice from the real world is to go raw, the over heads are minimal
>from an administration point of view, you just need to understand your
>platforms volume manager. The benefits are that you avoid double buffering
>in the unix and oracle cache. I've seen it improve system performance by
>up to 20%.
>

Er, read the Oracle performance tuning manual. As Oracle state: Always check your OWN system. ***Generally***, large block sizes and sequential reading (datawarehouse) performance is much worse under raw disks. My own testing mirrors the results in the Oracle Tuning guide.

>Oracle corporation recommend file system files for database files because
>they are platform independent and makes life easier for their consultants (
>they don't have to understand different suppliers volume managers.
>
>Phil

Actually they don't. The *general* recommendation in the latest Oracle manuals is to use RAW devices.

Steve Phelan. Received on Thu May 07 1998 - 10:03:35 CDT