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Re: Lost file-system story

On Sun, Dec 11, 2011 at 3:21 PM, Donald Allen 
<> wrote:
>>> More later ...
> I installed OpenBSD 5.0 on the same machine, similar setup (all
> filesystems noatime except /tmp and /home, which are both
> async,noatime). I repeated my experiment -- wrote a new file in my
> home directory, waited a few minutes, and killed the power. On reboot,
> there were complaints from the fscks, async and not, all fixed. The
> system came up without a manual fsck and the new file was present in
> my directory. So meta-data for async filesystems is being written
> within a window of a handful of minutes with OpenBSD.

I haven't read every single word you've said about this subject, so I
apologize if I'm missing something.

I assume you're using async because you want better performance and
you have some tolerance for data loss, otherwise this wouldn't even be
a discussion I think.

We're just talking about probabilities of data loss then, correct? For
some people (I suspect, a few that have already answered), this isn't
something they are willing to discuss, even though we all know it's
impossible to get to "1" as you said. But you can get really close
these days.

If solving your problem depends on sync frequency, I don't see why
this shouldn't be managed by some knob to twiddle. Given that the
crash scenario doesn't get worse depending on where the knob is or if
the crash happens while the knob is working. If it does, it's

Why haven't other solutions been discussed? NetBSD supports ext2. And
raid. And all kinds of other stuff. Why not use it?


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