md /tmp and async mounts

[Kris Kennaway]

On Sun, Jun 04, 2006 at 08:03:16AM +0300, Giorgos Keramidas wrote:
> On 2006-06-02 18:07, Kris Kennaway <kris at obsecurity.org> wrote:
> >On Fri, Jun 02, 2006 at 04:50:06PM -0500, Craig Boston wrote:
> >>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.
> >
> > Yeah, it's kind of a poorly chosen name.
> 
> Should we still revert the default from using -M for tmpmfs="YES" and
> varmfs="YES" in rc.conf?

Someone should test it in a situation without swap configured
(including what is the failure mode when you run out of memory -
probably a panic again), but it "should" be fine (i.e. behaves the
same or better than malloc in all situations).

Kris
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20060604/a8aeb206/attachment.pgp