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Re: Lost file-system story

On Fri, 9 Dec 2011 15:50:35 -0500
Donald Allen <> wrote:

> were not designed to do this. The reason I'm beating on this is that I
> would have liked to use NetBSD for the application I have in mind, but
> I need the performance improvement that async provides (my tests show
> this; the tests also show that NetBSD async is about as fast as Linux,
> much faster than OpenBSD async, at least for doing a lot of writing,
> such as un-tarring a large tar file). This is practical if the joint

The speed and reliability WAPBL provides have been enough for my uses
personally; are the few seconds saved using async really that worth the
trouble?  Also, if raw speed is needed to do many installations on
identical systems, dd with large blocks to mirror the system might be a
faster alternative...

I'm not argueing that fsck shouldn't be able to recover though; it
ideally should, but the problem seems to be that too much metadata is
missing when crashing while writing in async mode.

OpenBSD's async mode would be slightly slower while flushing metadata
more often, probably.  Perhaps that having a sysctl to control flushing
would be a good thing, though.


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