From owner-freebsd-fs@FreeBSD.ORG  Fri Feb 10 17:00:59 2012
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Date: Fri, 10 Feb 2012 19:37:31 +0300
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From: Sergey Kandaurov <pluknet@gmail.com>
To: Ed Schouten <ed@80386.nl>
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Cc: fs@freebsd.org
Subject: Re: Increase timestamp precision?
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On 10 February 2012 17:55, Ed Schouten <ed@80386.nl> wrote:
> Hi all,
>
> It seems the default timestamp precision sysctl
> (vfs.timestamp_precision) is currently set to 0 by default, meaning we
> don't do any sub-second timestamps on files. Looking at the code, it
> seems that vfs.timestamp_precision=1 will let it use a cached value with
> 1 / HZ precision and it looks like it should have little overhead.
>
> Would anyone object if I were to change the default from 0 to 1?
>

[Yep, sorry I didn't read this mail before replying to your another mail.]

I am for this idea. Increasing vfs.timestamp_precision will allow
to use nanosecond precision for all those *stat() and *times()
syscalls which operate on struct timespec.

FWIW, NetBSD uses only nanotime() inside vfs_timestamp() since its
initial appearance in 2006.

-- 
wbr,
pluknet