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Date:   Thu, 16 Jun 2022 15:27:40 -0700
From:   Mike Kravetz <mike.kravetz@oracle.com>
To:     Muchun Song <songmuchun@bytedance.com>
Cc:     Joao Martins <joao.m.martins@oracle.com>, david@redhat.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        linux-doc@vger.kernel.org, akpm@linux-foundation.org,
        corbet@lwn.net
Subject: Re: [PATCH 3/6] mm: hugetlb_vmemmap: introduce the name HVO
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On 06/16/22 11:28, Muchun Song wrote:
> On Wed, Jun 15, 2022 at 03:51:51PM +0100, Joao Martins wrote:
> > On 6/13/22 07:35, Muchun Song wrote:
> > > It it inconvenient to mention the feature of optimizing vmemmap pages associated
> > > with HugeTLB pages when communicating with others since there is no specific or
> > > abbreviated name for it when it is first introduced.  Let us give it a name HVO
> > > (HugeTLB Vmemmap Optimization) from now.
> > > 
> > 
> > Just thought I would throw this suggestion, even though I am probably too late.
> > 
> 
> Not too late, we are still discussing the name.
> 
> > I find the term "vmemmap deduplication" more self-explanatory (at least for me)
> > to refer to your technique ,and similarly s/optimize/dedup. Or vmemmap tail page
> > deduplication (too verbose maybe) because really that's what this optimization is all
> > about. OTOH it would slightly deviate from what maybe established now
> > in hugetlb code.
> >
> 
> Well, I have looked up this word "deduplication" which refers to a method of
> eliminating a dataset’s redundant data.  At least I agree with you "deduplication"
> is more expressive for my technique.  So I am thinking of renaming "HVO" to "HVD (
> HugeTLB Vmemmap Deduplication)".  In this series (patch 6), I have renamed
> hugetlb_vmemmap_alloc/free to hugetlb_vmemmmap_optimize/restore.  I am also
> thinking of replacing it to:
> 
>   hugetlb_vmemmmap_deduplicate vs hugetlb_vmemmmap_duplicate.
> 
> Many other places in hugetlb_vmemmap.c use "optimize" word, maybe most of them do
> not need to be changed since "deduplication" is also a __optimization__ technique.
> 
> Hi Mike and David:
> 
> What your opinion on this? I want to hear some thoughts from you.

I can understand Joao's preference for deduplication.  However, I can
also understand just using the term optimization.  IMO, neither is far
superior to the other.  It is mostly a matter of personal preference.

My preference would be to leave it as named in this series unless
someone has a strong preference for changing.
-- 
Mike Kravetz