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Date: Fri, 2 Jun 2006 16:50:06 -0500
From: Craig Boston <craig@xfoil.gank.org>
To: Giorgos Keramidas <keramida@ceid.upatras.gr>
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Cc: freebsd-current@freebsd.org, Kris Kennaway <kris@obsecurity.org>
Subject: Re: md /tmp and async mounts
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On Fri, Jun 02, 2006 at 12:35:27AM +0300, Giorgos Keramidas wrote:
> Ok, I'll prepare a patch that enables async and disables -M.  We should
> also document the fact that tmpmfs="YES" and varmfs="YES" in rc.conf may
> require the presence of at least one swap device by default, and point
> the users to -M with a warning if they run FreeBSD without a swap device
> but still want to use tmpmfs or varmfs :)

I may be mistaken, but from my (brief) reading of the code it seems to
me that perhaps "swap-backed" isn't an entirely accurate term.  More
like "VM-backed", with the understanding that VM is (usually) backed by
swap.

I think if you don't have any swap configured, a swap-backed md will be
no worse off than a memory-backed one would.

Craig