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Subject: Re: svn commit: r309714 -
 head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs
To: Alexander Motin <mav@FreeBSD.org>, src-committers@FreeBSD.org,
 svn-src-all@FreeBSD.org, svn-src-head@FreeBSD.org
References: <201612081558.uB8Fw4xA027508@repo.freebsd.org>
From: Andriy Gapon <avg@FreeBSD.org>
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Date: Wed, 14 Dec 2016 14:03:38 +0200
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On 08/12/2016 17:58, Alexander Motin wrote:
>   This change switches zio_timestamp_compare() from comparing uninitialized
>   io_offset to really populated io_bookmark values.  I haven't decided yet
>   what to do with timestampts, but on simple tests this change gives the
>   same peformance results by just making code to work as declared.

I think that we should just enable precise timestamps.
I just can't see them noticeably hurting performance given the amount of
calculations, memory allocations, locking, etc, that ZFS already has.
And there are layers above and below ZFS too.

-- 
Andriy Gapon