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Date:   Wed, 14 Apr 2021 20:00:02 -0700
From:   Andi Kleen <ak@linux.intel.com>
To:     Yu Zhao <yuzhao@google.com>
Cc:     Rik van Riel <riel@surriel.com>,
        Dave Chinner <david@fromorbit.com>,
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Subject: Re: [PATCH v2 00/16] Multigenerational LRU Framework
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> We fall back to the rmap when it's obviously not smart to do so. There
> is still a lot of room for improvement in this function though, i.e.,
> it should be per VMA and NUMA aware.

Okay so it's more a question to tune the cross over heuristic. That
sounds much easier than replacing everything.

Of course long term it might be a problem to maintain too many 
different ways to do things, but I suppose short term it's a reasonable
strategy.

-Andi