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From: Ivan Voras <ivoras@freebsd.org>
Date: Wed, 28 Aug 2013 12:31:35 +0200
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Subject: Re: svn commit: r254986 - head/sys/ufs/ufs
To: Davide Italiano <davide@freebsd.org>
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On 28 August 2013 12:25, Davide Italiano <davide@freebsd.org> wrote:

> do you have any evidence that this change impacts positively (or
> negatively) performances for some workloads? If yes, can you share?

Yes, observation of my own servers. Without this, dirhash is basically
useless since in certain situations everything gets evicted after 5
seconds and it never grows to its full potential.

> Also, why did you choose the '60' value (rather than something else)?

Personal experience.

> I don't see any 'Reviewed by:' line in your commit message neither I
> remember a public discussion on -current or -arch or -fs about this.
> OTOH I think such changes deserve a wider discussion.

See discussion in @stable.