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From: David Howells <dhowells@redhat.com>
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To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: dhowells@redhat.com, Thomas Gleixner <tglx@linutronix.de>,
        John Stultz <john.stultz@linaro.org>,
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Subject: Re: Apparent backward time travel in timestamps on file creation
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Date: Thu, 30 Mar 2017 20:35:28 +0100
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Linus Torvalds <torvalds@linux-foundation.org> wrote:

> The difference can be quite noticeable - basically the
> "gettimeofday()" time will interpolate within timer ticks, while
> "xtime" is just the truncated "time at timer tick" value _without_ the
> correction.

Is there any way to determine the error bar, do you know?  Or do I just make
up a fudge factor?

Obviously the filesystem truncation would need to be taken into account (and
this can be different for different timestamps within the same filesystem).

David