Re: Storage (EMC) layout advice..

We actually most likely won't even set db_block_multi_block_read_count high in regular operation (this is a transactional database), but at night we might set it high for batch jobs on per-session level.

During the day the parameter will equal to stripe unit (element) size, most likely, to discourage FTS.

-A

On Wed, 27 Jul 2005 21:31:03 +0200, "Matthias Hoys" <idmwarpzone_NOSPAM__at_yahoo.com> wrote:

>
>"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
>
>

.......
We use Oracle 8.1.7.4 and 9.2.0.5 on Solaris 2.7 boxes remove NSPAM to email Received on Wed Jul 27 2005 - 15:33:42 CDT