Re: What's better: ASMlib or RAW...

From: Cristian Cudizio <cristian.cudizio_at_yahoo.it>
Date: 11 May 2007 00:09:20 -0700
Message-ID: <1178867360.608403.56200@l77g2000hsb.googlegroups.com>

On May 11, 7:19 am, oracle_man <oracle_..._at_yahoo.com> wrote:
> Call to arms:
>
> I: What is the better choice on x86_64,RHEL4u4(2.6x kernel), EMC
> CX300 SAN, EMC powerpath 4.5x, Oracle 10.2.0.3.0, RAC, ASM?
>
> 1) ASMlib accessing block dev, asynch i/o
> 2) Raw device access via /dev/raw/rawX
>
> II: Which i/o scheduler do you use with each respective technology
> stack?
>
> 1) CFQ
> 2) Deadline
> 3) No-OP
> 4) Anticipator
>
> III: Last question: Which parameter do you use for the above?
>
> 1) DISK_ASYNCH_IO
> 2) FILESYSTEMIO_OPTIONS
On http://www.oracle.com/technology/tech/linux/validated-configurations/index.html you can find useful informations
i) Oracle recommends use of ASMlib for easy of management. In my opinion is not a great advantage, but on Kernel 2.6 Raw are deprecated,
(however if you use RAC whitout cluster filesystem you must use raw devices for ocr and voting).
ii) On validated configurations oracle suggest use of Deadline schedulator
iii) i use default values for DISK_ASYNCH_IO (that is true on my suse el9 installations) and FILESYSTEMIO_OPTIONS that is not relevent if you use ASM.

Bye
Cristian Cudizio

http://oracledb.wordpress.com
http://cristiancudizio.wordpress.com Received on Fri May 11 2007 - 02:09:20 CDT