Re: ASM disk sizes
Date: Mon, 8 Jul 2013 19:03:20 +0100
Message-ID: <CAKA5CbJKvo4QrEYFvSikhkqxd2o5OkKvK7S2=v+8yoPXK2YoQw_at_mail.gmail.com>
Hi David,
I'm sure you don't want to go there having different sizes for ASM disks. I personally have been there once - diskgroup needed rebalance, but few of the disks were already filled up so I had to drop temp tablespace to free up some space within the diskgroup and complete the rebalance.
I do not consider consistent disks as luxury, as a matter of fact I had that on all kind of storage systems, even entry level class. I'm not sure if by saying diskgroup they refer ASM diskgroup or else because with LVM volume groups you can have all kind of disks (after all that's the point of LVM). I would insist of having consistent disks even thin provisioned, but to be equally sized.
Regards,
Sve
On Mon, Jul 8, 2013 at 5:17 PM, Herring, David <HerringD_at_dnb.com> wrote:
> Folks,
>
> I'm running into a discussion with another DBA on our team concerning
> differing disk (or LUN, but for the sake of simplicity let's just say
> "disk") sizes within ASM. Best practices for ASM say to use consistent
> sizes of disks within a diskgroup and I'm sure many of us have run into
> situations where there was an inconsistency, the smallest disk filled and
> suddenly Oracle gave space errors even though there was plenty of space on
> the larger disks. That's just one example of issues that can arrise.
>
> Back to the discussion, I'm told that:
>
> 1) Having consistent disk sizes is a "luxury"
> 2) Many places have inconsistent disk sizes, within diskgroups,
> and work just fine.
>
> Do many of you currently or in the past worked on dbs where the disks were
> differently sized within diskgroups for ASM? Do most/any of you see
> consistent disks within diskgroups as a "luxury" and that instead you
> accept whatever the SAN team gives you?
>
> Even though I've run into issues concerning space with inconsistently
> sized disks on 10g and 11g and performed A LOT of detailed tracking of the
> arb processes doing their rebalance work, I'm being ignored. It's rather
> frustrating to say the least. In one diskgroup they've got disks of 511
> GB, 430 GB, 143 GB, and 122 GB. They're all about 32% used so the best as
> I can figure is rebalance operations weren't fully performed when disks
> were added.
>
> Dave Herring
>
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Mon Jul 08 2013 - 20:03:20 CEST