Re: Balance RAID10 with odd device count

[Gareth Pye <gareth@cerberos.id.au>]

I'd probably want to use DupeX to refer to what was classically RAID1
(Duplicate across all disks) and Dupe is an alias for Dup2 but one can
also choose Dupe3 through Dupe99

And I keep forgetting to post to the list in plain text, so many of
you may not have noticed my original email that only exists on the
mailing list in the Quotation in Tom's email

On Tue, Feb 21, 2012 at 12:59 PM, Tom Cameron <tomc603@gmail.com> wrote=
:
> Gareth,
>
> I would completely agree. I only use the RAID vernacular here because=
,
> well, it's the unfortunate defacto standard way to talk about data
> protection.
>
> I'd go a step beyond saying dupe or dupe + stripe, because future
> modifications could conceivably see the addition of multiple
> duplicated sets. The case of 4 disks in a BTRFS filesystem with dupe
> running across all of them would be a clear extension I could see. So
> that would be something like 4D. I'm not real sure what you'd use for
> the terminology, but something completely different than RAID-like
> terms is almost certainly best. Just look at the ZFS documentation to
> see how carefully they have to spell out what RAID-Z, Z2, and Z3 do
> because they used the RAID acronym.
>
> On Mon, Feb 20, 2012 at 8:47 PM, Gareth Pye <gareth@cerberos.id.au> w=
rote:
>> On Tue, Feb 21, 2012 at 12:07 PM, Tom Cameron <tomc603@gmail.com> wr=
ote:
>>>
>>> It seems from the BTRFS documentation that the RAID1 profile is
>>> actually "mirror", or store 2 copies of the object. Perhaps when
>>> Oracle makes BTRFS a production option they should more clearly spe=
ll
>>> that out.
>>
>>
>> I'd really like BTRFS to not use RAID level terminology anywhere (ot=
her than
>> maybe in=A0parenthesis=A0along the lines of: "this is similar to RAI=
DX") and use
>> less ambigious options as the recommended way to talk about things. =
As there
>> is good reason to talk about Dup and RAID1 differently as they aren'=
t the
>> same on more than 2 drives. Doing it that way will make people under=
stand
>> what is going on more often, which should be good.
>>
>> It also makes things much easier to remember. Like how much data can=
 you fit
>> on a 6 drive RAID10? I dunno, but I can more intuitively answer that=
 same
>> question when it is phrased as just simply 'dup', or maybe 'dup + st=
ripe'.
>>
>> Is there a difference in BTRFS between dup and raid10?
>>
>> --
>> Gareth Pye
>> Level 2 Judge, Melbourne, Australia
>> Australian MTG Forum:=A0mtgau.com
>> gareth@cerberos.id.au=A0-=A0www.rockpaperdynamite.wordpress.com
>> "Dear God, I would like to file a bug report"
>>



--=20
Gareth Pye
Level 2 Judge, Melbourne, Australia
Australian MTG Forum:=A0mtgau.com
gareth@cerberos.id.au=A0-=A0www.rockpaperdynamite.wordpress.com
"Dear God, I would like to file a bug report"
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