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Date:   Wed, 11 Jan 2023 18:37:05 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     David Laight <David.Laight@aculab.com>,
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Subject: Re: [PATCH 08/41] mm: introduce CONFIG_PER_VMA_LOCK
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On Wed 11-01-23 09:04:41, Suren Baghdasaryan wrote:
> On Wed, Jan 11, 2023 at 8:44 AM Michal Hocko <mhocko@suse.com> wrote:
> >
> > On Wed 11-01-23 08:28:49, Suren Baghdasaryan wrote:
> > [...]
> > > Anyhow. Sounds like the overhead of the current design is small enough
> > > to remove CONFIG_PER_VMA_LOCK and let it depend only on architecture
> > > support?
> >
> > Yes. Further optimizations can be done on top. Let's not over optimize
> > at this stage.
> 
> Sure, I won't optimize any further.
> Just to expand on your question. Original design would be problematic
> for embedded systems like Android. It notoriously has a high number of
> VMAs due to anonymous VMAs being named, which prevents them from
> merging.

What is the usual number of VMAs in that environment?

-- 
Michal Hocko
SUSE Labs