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Date: Thu, 10 Aug 2006 16:05:35 -0500
From: Craig Boston <craig@xfoil.gank.org>
To: Pawel Jakub Dawidek <pjd@FreeBSD.org>
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Cc: freebsd-fs@FreeBSD.org, freebsd-current@FreeBSD.org,
	freebsd-geom@FreeBSD.org
Subject: Re: GJournal (hopefully) final patches.
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On Thu, Aug 10, 2006 at 09:28:41PM +0200, Pawel Jakub Dawidek wrote:
> When you mount file system it sends BIO_GETATTR "GJOURNAL::provider"
> requests. So as long as classes between the file system and gjournal
> provider pass BIO_GETATTR down, it will work.
> 
> I prefer to put gjournal on the top, because it gives consistency to
> layers below it. [...]
>
> [snip]
> 
> Fortunatelly with GEOM you can freely mix your puzzles.

Would there be any ill effects to putting multiple filesystems inside a
single gjournal, say with a bsdlabel or gpt on it?

If it worked and didn't confuse the UFS integration, it might save some
space by not having multiple (default 1G) journals.  I'm unsure if it
would improve or degrage performance for concurrent access.

Craig