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Date:   Sat, 22 Jan 2022 01:41:31 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     "Longpeng (Mike, Cloud Infrastructure Service Product Dept.)" 
        <longpeng2@huawei.com>
Cc:     Khalid Aziz <khalid.aziz@oracle.com>,
        Barry Song <21cnbao@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        David Hildenbrand <david@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>, Mike Rapoport <rppt@kernel.org>,
        Suren Baghdasaryan <surenb@google.com>
Subject: Re: [RFC PATCH 0/6] Add support for shared PTEs across processes
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On Sat, Jan 22, 2022 at 01:39:46AM +0000, Longpeng (Mike, Cloud Infrastructure Service Product Dept.) wrote:
> > > Our use case is that we have some very large files stored on persistent
> > > memory which we want to mmap in thousands of processes.  So the first
> 
> The memory overhead of PTEs would be significantly saved if we use
> hugetlbfs in this case, but why not?

Because we want the files to be persistent across reboots.