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Subject: Re: [PATCH] mm, swap: Make VMA based swap readahead configurable
To: "Huang, Ying" <ying.huang@intel.com>, Michal Hocko <mhocko@kernel.org>
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Cc: Minchan Kim <minchan@kernel.org>,
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From: Dave Hansen <dave.hansen@intel.com>
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On 09/27/2017 06:02 PM, Huang, Ying wrote:
> I still think there may be a performance regression for some users
> because of the change of the algorithm and the knobs, and the
> performance regression can be resolved via setting the new knob.  But I
> don't think there will be a functionality regression.  Do you agree?

A performance regression is a regression.  I don't understand why we are
splitting hairs as to what kind of regression it is.

Are you only willing to fix it if it's a functional regression?