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Date: Mon, 18 Jun 2007 09:44:36 -0700
From: John Polstra <jdp@polstra.com>
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To: Xin LI <delphij@delphij.net>
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Cc: freebsd-fs@FreeBSD.org, freebsd-current@FreeBSD.org
Subject: Re: Why vfs.timestamp_precision is set to 0 by default?
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Xin LI wrote:

> Recently while I'm looking into the VFS code I found that we set
> vfs.timestamp_precision to 0 by default.  Is there any reason not to set
> this to, for instance 1 by default?  My rough test indicates that the
> performance affect is almost negligible...

If I remember correctly, I set the default to 0 for compatibility -- 
i.e., so that the fractional seconds would continue to be set to 0 as 
before.  That was probably too conservative.

John