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Date: Wed, 17 Nov 2004 14:29:26 -0600
From: Dan Nelson <dnelson@allantgroup.com>
To: David Gilbert <dgilbert@dclg.ca>
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cc: freebsd-hackers@freebsd.org
Subject: Re: Access time on snapshots.
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In the last episode (Nov 17), David Gilbert said:
> Another odd thing about snapshots is that the time shown by ls -l is
> mostly current.  Havn't found a rule for that yet.  ls -lu seems to
> show the creation time even tho the man page for ls says that's the
> last access time.
> 
> Since the snapshot itself shouldn't (logically) change after
> creation, it would seem sensible to make the modification time stay
> constant.

Could the mtime on the snapshot might be updated when the kernel has to
add a block to the snapshot file because of a write to the parent
filesystem? (note this only applies to the first write to a block;
later writes don't affect the snapshot because it's already made a copy
of the original data)

> (also: why doesn't ls have a creation time option?)

I think ls is running run out of option letters :)

-- 
	Dan Nelson
	dnelson@allantgroup.com