Re: Storage (EMC) layout advice..

From: Matthias Hoys <idmwarpzone_NOSPAM__at_yahoo.com>
Date: Wed, 27 Jul 2005 21:31:03 +0200
Message-ID: <42e7e0f9$0$30475$ba620e4c@news.skynet.be>

"NetComrade" <netcomradeNSPAM_at_bookexchange.net> wrote in message news:42e7c437.700706828_at_localhost...
> On 26 Jul 2005 17:04:05 -0700, bdbafh_at_gmail.com wrote:
>
>>I'm partial to 8 disk RAID 10 volumes for datafiles.
>>how about if you create one on each tray for datafiles and stripe
>>across those?
>>you could then use the remaining 7 drives per tray for 4 disk RAID 10
>>and 2 disk RAID 1 vols with a hot spare.
>>Aim for a 1 MB stripe on the 8 disk RAID 10 vols, as your OS supports
>>that for a max IO size and based upon your db_block_size (or the block
>>size for each tablespace) and the dbfmbrc oracle should be able to
>>issue 1 MB read requests - in theory.
>
> Do you know if OS supports higher than 1M?
> db_block_multi_block_read_count can be set to any number.. that
> doesn't mean OS will support it.
>

And higher values for DMBRC might "cheapen" the use of full-table scans instead of indexes so that could be a non-optimal side-efffect.

Matthias Received on Wed Jul 27 2005 - 14:31:03 CDT