RE: To use SAME or NOT for High End Storage Setup ? .... StripeUnit Size 32 MB Vs. 64 KB ?

Home -> Community -> Mailing Lists -> Oracle-L -> RE: To use SAME or NOT for High End Storage Setup ? .... StripeUnit Size 32 MB Vs. 64 KB ?

From: Kevin Closson <kevinc_at_polyserve.com>
Date: Mon, 15 May 2006 07:49:29 -0700
Message-ID: <5D2570CAFC98974F9B6A759D1C74BAD0E5A3E6@ex2.ms.polyserve.com>

 >>>array. In both cases performance was fine and there were no "hot"

>>>disks. The logic for choosing 4 MB was to ensure that any
>>>full table scans (in our case 128 KB) would avoid having the
>>>multi-block reads split into two reads due to the required
>>>blocks existing in more than 1 "stripe".

a 4MB stripe width will reduce the odds there will be cross-stripe reads, but in no way eliminates it. The planets do not align that way.

>>>
>>>IMHO I'm not sure why IBM are recommending why you should go
>>>as large as 32 MB.

I'm still surprised to hear there is such a thing as a 32MB stripe width on a DSXXXX array... maybe they meant 32KB (which would be a trainwreck) ?

--
http://www.freelists.org/webpage/oracle-l

Received on Mon May 15 2006 - 09:49:29 CDT