| 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: Data Warehousing - RAID5 or RAID0-1
> Channel #1 Oracle data 150GB and he says that the other
> Channel #2 is used for mirroring. My question is that in
> this case as far is Oracle is concerned will it see one
> channel or 2 channels?
>
> If it is one channel wouldn't there be contention at the
> channel (controller) level.
>
If I understand it correctly.
I think you are being provided with ONE 150G disk volume for Oracle and as you say this will cause contention. It doesn't matter how you split it up into logical volumes /u0, /u1/... as it is effectively all on the same hard disk.
This is NOT a good idea.
The spread of tablespaces needs to be done at a physical level e.g. if you have 10 * 18 gig disks availble they should be split into multiple volumes of
4 * 18, 4 * 18, 2 * 18,
not 10 * 18.
George.
> -----Original Message-----
> From: "Surjit Sharma" <surjits_at_ozemail.com.au>
> [mailto:surjits_at_ozemail.com.au]
> Sent: Saturday, May 06, 2000 1:44 PM
> To: smtp_at_inl001@servers["Multiple recipients of list ORACLE-L"
> <ORACLE-L_at_fatcity.com>]
> Subject: Re: Data Warehousing - RAID5 or RAID0-1
>
>
> RE: Data Warehousing - RAID5 or RAID0-1Thanks guys.
>
> I am really overwhelmed with the depth of knowledge out there.
> It clears a lot my doubts and hopefully avoid being taken for
> a ride by the SA and Co.
>
> From the discussions I gather that RAID0+1 is the way to go.
>
> Current Scenario
> ============
> For the Test box (Oracle Data 150 GB) my SA tells me that
> there is one internal channel and 2 external channels. I
> believe the only two external channels are available for oracle data.
>
> And this is how the SA proposes to configure :
>
> Channel #1 Oracle data 150GB and he says that the other
> Channel #2 is used for mirroring. My question is that in
> this case as far is Oracle is concerned will it see one
> channel or 2 channels?
>
> If it is one channel wouldn't there be contention at the
> channel (controller) level.
>
> I am confused as to whether you need two channels per area eg
> Data (Channel 1 Data , Channel 2 for Mirrored Data [Striped]
> ) or One channel itself will have data and mirrored data
> [Striped] ) underneath.
>
> Future
> =====
> Ideally it appears that you need at least 4 channels
> (assuming mirroring and striping is taken care of by some
> other channels automatically) to spread your data , index
> ,rbs,temp and redo logs. This is how I see the physical
> layout of the data.
>
> Channel #1 Data , redo
> Channel #2 Index ,redo
> Channel #3 Rollback Segment and Temp
> Channels # 4 Redo Logs
>
> Really in this case do I need 4 channels or 8 channels.
>
> Your response is highly appreciated.
>
> Thanks
>
> Surjit
>
>
> ----- Original Message -----
> From: Alex Hillman
> To: Multiple recipients of list ORACLE-L
> Sent: Saturday, May 06, 2000 10:16 AM
> Subject: RE: Data Warehousing - RAID5 or RAID0-1
>
>
> This makes sence - to have RAID 5 for historical (only
> read) data. For everythig else - RAID 0+1.
>
> Alex Hillman
>
> -----Original Message-----
> From: Madhavan Amruthur [mailto:mad012000_at_hotmail.com]
> Sent: Friday, May 05, 2000 5:56 PM
> To: Multiple recipients of list ORACLE-L
> Subject: RE: Data Warehousing - RAID5 or RAID0-1
>
>
>
> Hi Alex,
> Its been almost a year and half since we did this and I
> went back and
> checked how we laid it out.
> I just checked the spreadsheet, we had RAID 1 for TEMP,
> current fact table
> data and index data.
> We had RAID 5 for historical fact and index data.
> We had RAID 0+1 set up for RBS, redo logs and dimesion table data.
>
> This was a set up that we built at that time and this was a
> benchmarking
> system and no new data was being added at that time except
> we were loading
> the aggregates based on the data available.
>
> This probably was not the best layout but for our scenario
> this worked
> pretty well and within the limitations of the resources we had.
>
> Hope this helps.
> Regards,
>
> Madhavan
> IBM Corporation Webserver Division
>
>
>
> >From: Alex Hillman <alex_hillman_at_physia.com>
> >Reply-To: ORACLE-L_at_fatcity.com
> >To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
> >Subject: RE: Data Warehousing - RAID5 or RAID0-1
> >Date: Fri, 05 May 2000 12:48:56 -0800
> >
> >But doesn't moving involve writing (into data tablespaces,
> indexes or index
> >creation)? In this case what did you win? I think that if
> you can not
> >afford
> >to have everything in RAID 0+1 you should have RBS, TEMP,
> REDO LOGS and
> >most
> >often changing data and indexes on RAID 0+1. By the way,
> the difference
> >between let say 1TB of RAID 5 and RAID 0+1 is 0.8TB of
> disk space. If we
> >assume that 10G disk cost $500 then 0.8TB should cost
> $40,000. It is
> >nothing
> >comparing with other costs of 1TB DW. Any thoughts anybody?
> >
> >Alex Hillman
> >
> >-----Original Message-----
> >Sent: Friday, May 05, 2000 2:03 PM
> >To: Multiple recipients of list ORACLE-L
> >
> >
> >RAID-5 should be good for the DW application but the area
> where information
> >is loaded (involves lot of writes), we loaded them in a
> RAID 1 area and
> >then
> >
> >we moved them over to the RAID-5 area as RAID-1 is good
> for writes.
> >
> >Hope this helps.
> >Regards,
> >
> >Madhavan
> >
> >
> > >From: CHUCK_HAMILTON_at_qvc.com
> > >Reply-To: ORACLE-L_at_fatcity.com
> > >To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
> > >Subject: Re: Data Warehousing - RAID5 or RAID0-1
> > >Date: Fri, 05 May 2000 07:39:58 -0800
> > >
> > >
> > >DWs are typically high read, low write applications.
> RAID-5 should be
> >fine
> > >for all but TEMP tablespace, RBS tablespace, redo logs,
> and archived
> >logs.
> > >RAID 0+1 is also good but requires twice as much disk.
> > >--
> > >Chuck Hamilton
> > >QVC Inc.
> > >Enterprise Technical Services
> > >Oracle DBA
> > >
> > >
> > >
> > > "Surjit
> > > Sharma" To:
> Multiple recipients of
> > >list ORACLE-L <ORACLE-L_at_fatcity.com>
> > > <surjits_at_ozema cc: (bcc: CHUCK
> > >HAMILTON/QVC)
> > > il.com.au> Subject:
> Data Warehousing
> >-
> > >RAID5 or RAID0-1
> > > Ext: NA
> > > Sent by:
> > > root_at_fatcity.c
> > > om
> > >
> > >
> > > 05/05/00 09:14
> > > AM
> > > Please respond
> > > to ORACLE-L
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >Hi
> > >
> > >I need your thoughts on RAID0-1 vs RAID5 configuration
> on very large
> >data
> > >warehousing project. The expected data is going to be
> about 1 Tera byte,
> > >10 Giga byte Memory, Sun box E6500 , Oracle 8.1.5.
> > >
> > >I am told that for data warehousing RAID01 (mirroring
> and striping) is
> >the
> > >good balance between RAID5 and no RAID at all. Does
> anyone has any
> > >experience on this? I will be delighted to hear your thoughts.
> > >
> > >My main consideration is to be able to load the data in
> the given window
> > >(overnight) and good response time for the queries.
> > >
> > >Thanks in advance.
> > >
> > >Surjit
> > >
> > >
> > >
> > >
> > >--
> > >Author:
> > > INET: CHUCK_HAMILTON_at_qvc.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).
> >
>
> >_____________________________________________________________
> ___________
> >Get Your Private, Free E-mail from MSN Hotmail at
http://www.hotmail.com
> >-- >Author: Madhavan Amruthur > INET: mad012000_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). ________________________________________________________________________Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
--
Author: Madhavan Amruthur
INET: mad012000_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 Received on Mon May 08 2000 - 04:07:32 CDT
 |
 |