On gjournal vs unexpected shutdown (-->fsck)

[Hywel Mallett]

On 8 Dec 2009, at 22:47, Andrew Reilly wrote:

> Hi there,
> 
> I thought that I'd try a gjournal'd UFS on one of my spare
> drives (so: dedicated to the task, formatted from clean, per the
> instructions in the gjournal man page.)  The filesystem itself
> seems to be working swimmingly, although it isn't heavily used.
> In the time that I've had it running, though, I've had two power
> outages that have resulted in unexpected shutdowns, and I was
> surprised to find that the boot process did nothing unexpected:
> file system not marked clean: fsck before you can mount.  So
> both times I fsck'd the drive, and as near as I can tell this
> took exactly as long as fsck on a regular UFS system of similar
> size.  Isn't the journalling operation supposed to confer a
> shortcut benefit here?  I know that the man page doesn't mention
> recovery by journal play-back, but I thought that it didn't need
> to: that's the whole point.  Is there a step that I'm missing?
> Perhaps a gjournal-aware version of fsck that I should run
> instead of regular fsck, that will quickly mark the file system
> clean?
> 
> (Running -current as of last weekend, if that matters.)
> 
I assume you've run tunefs -J enable on the filesystems on the journalled provider? Or used newfs with -J if it's a new filesystem?
If I remember correctly it's this flag that fsck checks to see whether fsck is needed or not.
You can check whether the flag is set or not by running dumpfs on the filesystem. Under "flags" it'll say gjournal if the flag is set.