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Date: Sun, 1 Aug 2010 09:25:29 -0400
From: Jeff Layton <jlayton@redhat.com>
To: utz lehmann <lkml123@s2y4n2c.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Jeremy Allison <jra@samba.org>, Volker.Lendecke@sernet.de,
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Subject: Re: [PATCH 02/18] xstat: Add a pair of system calls to make
 extended  file stats available [ver #6]
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On Fri, 30 Jul 2010 23:22:58 +0200
utz lehmann <lkml123@s2y4n2c.de> wrote:

> On Thu, 2010-07-22 at 09:40 -0700, Linus Torvalds wrote:
> > But the fact is, th Unix ctime semantics are insane and largely
> > useless. There's a damn good reason almost nobody uses ctime under
> > unix.
> > 
> > So what I'm suggesting is that we have a flag - either per-process or
> > per-mount - that just says "use windows semantics for ctime".
> 
> When abusing an existing time stamp use atime not ctime please.
> ctime has it's uses. atime was just a mistake and is nearly useless.
> 
> And with noatime we already have creation time semantics for atime.
> 

Ugh. Honestly all of this talk of abusing different time fields seems
like craziness to me. It's going to be very hard to do that without
breaking *something*. There's also very little reason to do this when
xattrs are a much cleaner approach.

Neil Brown has put forth a very reasoned justification for putting the
birthtime in an xattr. After reading it, I think that makes more sense
than anything. It's also something that can be done without any extra
infrastructure. If at some point in the future we get an xstat-like
syscall then we can always add birthtime to that as well.

Ditto for the other fields under discussion (i_generation and the like).

-- 
Jeff Layton <jlayton@redhat.com>
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