RE: DBW0 and RAID5

RE: DBW0 and RAID5

 

  

"Never use raid 5 on Oracle OLTP DB" is SO NOT TRUE now a days. Although RAID 3 or 5 is certainly NOT the best choice for redo or temp tablespaces, many of todays RAId subsystems with proper config and caching can perform quite nicely. I have a test system where then ENTIRE db/app is on ONE RAID 5 and it runs very well considering it's just test. If you have the hardware and dollars, yada yada yada, go ahead and config RAID 0, 0+1, 10, or whatever. Not all companies can nor is it always appropriate. If you are trying to squeeze every drop of performance out of the system and can do/afford a mirror/stripe, then by all means do so. But to say NEVER, just incites rants like this one...

>>> "Givon Yoav " <oracledba-ezmlmshield-x88333983.[Email address protected] 06/02/04 06:42AM >>>
Never use raid 5 on Oracle OLTP DB. Calculating the CRC cost U numerous
CPU cycles and will slow down your write I/O operations. Use striping
and mirroring instead (Raid 0+1).

Use more then one DBW if your existing one is exhausted BUT your I/O sub
system can handle the extra I/O of the second DBW. Definably not the
case in Raid 5 environment.


Yoav


-----Original Message-----
From: Aldo Judeel
[mailto:oracledba-ezmlmshield-x92441541.[Email address protected]
Sent: Wednesday, June 02, 2004 11:19 AM
To: LazyDBA.com Discussion
Subject: DBW0 and RAID5

Can anyone please tell me if more that one DBW process will be a benefit

On a RAID5 system with only one CPU?



Tkanks

Aldo



--------
website: http://www.LazyDBA.com
Please don't reply to RTFM questions
Oracle documentation is here: http://tahiti.oracle.com
To unsubscribe: see http://www.lazydba.com/unsubscribe.html
To subscribe: send a blank email to oracledba-[Email address protected]
By using this list you agree to these
terms:http://www.lazydba.com/legal.html



--------
website: http://www.LazyDBA.com
Please don't reply to RTFM questions
Oracle documentation is here: http://tahiti.oracle.com
To unsubscribe: see http://www.lazydba.com/unsubscribe.html
To subscribe: send a blank email to oracledba-[Email address protected]
By using this list you agree to these terms:http://www.lazydba.com/legal.html



Oracle LazyDBA home page