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Date: Tue, 18 Aug 2009 14:55:05 +0300
From: Andriy Gapon <avg@freebsd.org>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: freebsd-arch@freebsd.org
Subject: Re: on architecture of dumping
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on 18/08/2009 13:59 Poul-Henning Kamp said the following:
> In message <4A8A85ED.4090404@freebsd.org>, Andriy Gapon writes:
>> I think that the following is quite obvious, but it needs to be said anyway.
>>
>> I think that we should switch from current approach of hierarchically
>> configuring dumper to having a hierarchy of dumpers.
> 
> I think this is utterly wolly thinking.

'wolly'? Please improve my English.

> The amount of complexity this will impose is staggering, and the potential
> benefit is no where close to justifying it.

I can't see the staggering complexity in the proposal, could you please expand?
Example of what I had in mind (pseudo-code):

static int
gmirror_dump(this, void *data, off_t offset, size_t size)
{
	LIST_FOREACH(pp, ...) {
		DUMP(pp, data, offset, size);
	}
}

> Add a cheap ATA disk for your dumps or make an USB stick work for dumps
> and use that.

Say, I do want mirrored dumps and/or I do want encrypted dumps - wouldn't it be
logical to re-use GEOM capabilities here.

-- 
Andriy Gapon