ADSM-L

Re: Using FILE instead of DISK devclass to avoid disk under-utilization

2006-10-26 08:39:33
Subject: Re: Using FILE instead of DISK devclass to avoid disk under-utilization
From: "Bos, Karel" <Karel.Bos AT ATOSORIGIN DOT COM>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Thu, 26 Oct 2006 14:35:32 +0200
Hi,

Reading the threat and missing something. Why another stg? 

For normal backup data I like to use JBOD config. No read protection at
all and maximum usable GB per disk. In order to minimize the number of
storage pools needed, ITSM 5.3 has the collecation by group option.

So, my 5.2 config is JBOD and more stg pools. My 5.3 config is less stg
pools and collocation groups. 

Regards,

Karel



-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Daniel Clark
Sent: donderdag 26 oktober 2006 13:52
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: Using FILE instead of DISK devclass to avoid disk
under-utilization

On 10/26/06, Roger Deschner <rogerd AT uic DOT edu> wrote:
> You probably want to avoid RAID5 for disk storage pools, whether 
> sequential or random. That can really slow client backups, because 
> RAID5 is quite slow for writing. RAID5 is really only good for 
> read-mostly applications, so at least you'll migrate quickly. You 
> probably want RAID10 instead, a striped set of mirrored pairs. (Make 
> sure your RAID10 implementation is NOT a mirrored pair of striped 
> sets, which is quite
> unsafe!) RAID10 is a less efficient use of raw disk space, but both 
> faster and safer than RAID5.

Yes, in a world of infinite funding, we would all use RAID1 or RAID10
:-)

Sadly I do not work in such an environment, so the choice was RAID1 and
not enough disk pool to possibly hold a night's backups, or RAID5 with
(barely) enough space... I choose the later option, and this thread is
about me trying to keep the (barely) bit intact.

--
Daniel Joseph Barnhart Clark
http://www.pobox.com/users/dclark

Attachment: disclaimer.txt
Description: Text document