DragonFly kernel List (threaded) for 2009-03
Re: 0byte files after crash
Dmitri Nikulin wrote:
> I agree, but if it is practical to implement behaviour similar to
> ext3's "data=ordered" for UFS soft updates, then that is certainly a
> good measure.
That's easy: Just switch soft-updates off and mount the
file system with the "sync" option. Of course it will be
much slower then, but that's how UFS works. It's not a
journaling file system. For a journaling file system,
the situation is different.
And of course, without soft-updates, you increase the risk
of introducing file-system inconsistencies upon crashes.
I agree with the people that argue that the applications
need to be fixed. Note that critical applications like
MTAs and most editors are already safe; they call fsync()
before closing a file and when renaming files. The latter
is especially important when a file is updated by creating
a temporary copy and then moving it over the old file. If
you don't sync, you might lose _both_ files after a crash.
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