| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
 |
 | |||
| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
|
| |||
Home -> Community -> Mailing Lists -> Oracle-L -> RE: RE: RAID or NOT to RAID?
Raid 5 suffers almost as much as 60% performance hit on writes. On reads
there is none.
Generally if you are using a mainly read only database, Raid 5 has no
negative side effects.
When the amount of writes increases, so doesn't the performance concerns
with Raid 5.
If you are talking about software raid on NT, double your performance
problem.
NT has very poor software raid, and the performance gain of the extra
spindles is almost non-apparent.
Raid 0+1 and Raid 1 is generally a good choice for Oracle databases, but it
depends on the mount point activity.
Although Raid 0+1 and Raid 1 both incur significantly higher costs due to
the increase in disks needed to get the same amount of space. But disks are
cheap and the performance difference is great.
But if you feel performance is not a major concern, cost is a concern, you are not doing high amounts of writes then Raid 5 is certainly an option. I rarely use Raid 5, but I will not blanket policy remove it from my list of tools. There are certainly a few environments it is the best option.
When you are stuck to very few disks, S.A.M.E. is also an alternative, although I am not a big advocate of S.A.M.E. in some small environments it may be the best choice.
"Do not criticize someone until you walked a mile in their shoes, that way when you criticize them, you are a mile a way and have their shoes."
Christopher R. Spence OCP MCSE MCP A+ RAPTOR CNA
Oracle DBA
Phone: (978) 322-5744
Fax: (707) 885-2275
Fuelspot
73 Princeton Street
North, Chelmsford 01863
-----Original Message-----
Sent: Wednesday, August 08, 2001 2:48 PM
To: Multiple recipients of list ORACLE-L
Hi DBA's,
I hope I'm not opening a can of worms, but I'd like your feedback on the
issue of using RAID 5 on NT 4.0 with Oracle 8.0.5.
I have worked with Solaris and RDBMS before switching to this job using the
NT platform. So I'm having to adjust and revisit the issues that was of
concern on the unix platform.
The NT and RAID configuration does not allow you to locate your datafiles
and logs on seperate specific disks. Also I don't know if the use of raw
devices on NT is possible if RAID 5 is enabled.
I've read about the performance loss inherent with RAID 5 because of the
writes to the parity disk.
I'd like to find out more about these issues and how you all are dealing
with them on the NT 4.0 platform?
Thanks in advance for your time.
Regards,
"Knowledge is power, but it is only useful if it is shared!"
>From: Paula_Stankus_at_doh.state.fl.us
>To: "LazyDBA.com Discussion" <oracledba_at_lazydba.com>
>Subject: RE: RAID or NOT to RAID?
>Date: Tue, 7 Aug 2001 13:22:48 -0400
>
>Can you forward me the info. you received on this? I am wondering
>about
>the
>issue as well - esp. as regards threads.
>
>-----Original Message-----
>From: Michael Porter [mailto:MPorter_at_pgahq.com]
>Sent: Tuesday, August 07, 2001 8:33 AM
>To: LazyDBA.com Discussion
>Subject: RAID or NOT to RAID?
>
>
>I don't want to start the proverbial war over RAID use in general but,
>I am seriously considering using RAID-10 (stripping + mirroring) for an
>Oracle 11.x application (AIX 4.3.3 and at least 8.0.5.2.1 db). IF I
>have several (more than 2) RAID10's and put redo on non raid volumes am
>I likely to get nearly as good performance with this as opposed to just
>straight mirroring OR individual volumes, possible stripped?
>
>Any points to other documentation or threads would be appreciated.
>
>Thanks,
>
>Mike
>
>
>--------
>Oracle documentation is here:
>http://tahiti.oracle.com/pls/tahiti/tahiti.homepage
>To unsubscribe: send a blank email to oracledba-unsubscribe_at_LAZYDBA.com
>To subscribe: send a blank email to oracledba-subscribe_at_LAZYDBA.com
>Visit the list archive: http://www.LAZYDBA.com/odbareadmail.pl
>Tell yer mates about http://www.farAwayJobs.com
>By using this list you agree to these
>terms:http://www.lazydba.com/legal.html
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Denmark Weatherburne INET: denmark_weatherburne_at_hotmail.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Christopher Spence INET: cspence_at_FuelSpot.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Wed Aug 08 2001 - 15:44:23 CDT
 |
 |