On Thu, Dec 20, 2007 at 11:34:10PM +0300, Dmitry Morozovsky wrote:
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> Hi there Pawel and colleagues,
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> am I right in thinking that there's currently no way to iron gnop provide=
r in=20
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> meta-data?
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> I'm thinking of creating the following geom tree:
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> ad{4,6,8,10,12}f
> |
> +> raid3/r0f --+
>                |
> ad12b          |
> |              |
> +> ad12b.nop --+
>                +> r0f.journal
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> because journal sector size should be equal to data sector size, which is=
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> this case 2k.
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> ad{4,6,8,10}b are used as two gmirrored swaps
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> Any thoughts/hints? Thanks in advance.

I'd just create small partition at the begining of raid3/r0f for
journal. What you propose is not best because:
1. Journal is on the same disk as one of the RAID components.
2. Journal is not protected with RAID - ad12 dies and your whole system
   will die.

My suggestion is to create small (~2GB) raid3/r0fa and big raid3/r0fd.
Then use raid3/r0fa as journal provider and raid3/r0fd as data provider.

--=20
Pawel Jakub Dawidek                       http://www.wheel.pl
pjd@FreeBSD.org                           http://www.FreeBSD.org
FreeBSD committer                         Am I Evil? Yes, I Am!