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Date:   Tue, 26 Sep 2023 14:09:55 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Stefan Roesch <shr@devkernel.io>
Cc:     David Hildenbrand <david@redhat.com>, kernel-team@fb.com,
        hannes@cmpxchg.org, riel@surriel.com, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH v3 1/4] mm/ksm: add "smart" page scanning mode
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On Tue, 26 Sep 2023 09:13:31 -0700 Stefan Roesch <shr@devkernel.io> wrote:

> > Thinking about it, what are the cons of just enabling this always and not
> > exposing new toggles? Alternatively, we could make this a compile-time option.
> >
> > In general, LGTM, just curious if we really have to make this configurable.
> >
> 
> The only downside I can see is that it might take a longer time for some
> pages to be de-duplicated (a new candidate page is added, but its
> duplicate is skipped in this round). So it will take longer to
> de-duplicate this page.
> 
> I tested with more than one workload, but it might be useful to get some
> data with additional workloads. I was thinking of enabling it after one or
> two releases.

We could keep the tunable and make it default "on"?