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Date: Wed, 16 May 2012 20:44:32 -0700
From: "H. Peter Anvin" <hpa@kernel.org>
Organization: Linux Kernel Organization, Inc.
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To: Linus Torvalds <torvalds@linux-foundation.org>
CC: Sasha Levin <levinsasha928@gmail.com>, Kay Sievers <kay@vrfy.org>,
        Greg KH <gregkh@linuxfoundation.org>, Yinghai Lu <yinghai@kernel.org>,
        Joe Perches <joe@perches.com>, Ingo Molnar <mingo@kernel.org>,
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Subject: Re: [PATCH RESEND 1/3] printk: convert byte-buffer to variable-length
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On 05/12/2012 11:35 AM, Linus Torvalds wrote:
> 
>  (b) The one thing I have often wanted is not "after how many seconds
> of boot", but "when". So it would actually be nice if the absolute
> time was converted into local time. The kernel can actually do that,
> so I suspect that the best format for the relative timestamps would
> really be something like
> 
>    > [May12 11:27] foo
>    > [May12 11:28] bar
>    > [  +5.077527] zoot
>    > [ +10.235225] foo
>    > [  +0.002971] bar
>    > [May12 11:29] zoot
>    > [  +0.003081] foo
> 
> because that would be really useful sometimes.
> 
> (And no, never mind the year. If you log those things long-term, the
> year will be in the full log, so logging the year in the dmesg is just
> pointless.)

I would like to give a +1 on absolute time, and -1 on local timezone and
a -$LARGE_NUMBER on low resolution.

Why?  Getting events accurately timed across multiple hosts can be
really useful when trying to reconstruct, ahem, "network events".

Getting UTC time at some fairly high resolution is useful for that.  I
would say the useful resolution is probably milliseconds.

	-hpa