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Date:   Fri, 4 Oct 2019 11:02:22 -0700 (PDT)
From:   David Rientjes <rientjes@google.com>
To:     Michal Hocko <mhocko@kernel.org>
cc:     Vlastimil Babka <vbabka@suse.cz>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mel Gorman <mgorman@suse.de>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>
Subject: Re: [rfc] mm, hugetlb: allow hugepage allocations to excessively
 reclaim
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On Fri, 4 Oct 2019, Michal Hocko wrote:

> Requesting the userspace to drop _all_ page cache in order allocate a
> number of hugetlb pages or any other affected __GFP_RETRY_MAYFAIL
> requests is simply not reasonable IMHO.

It can be used as a fallback when writing to nr_hugepages and the amount 
allocated did not match expectation.  Again, I'll defer all of this to 
Mike when he returns: he expressed his preference, I suggested an 
alternative to consider, and he can make the decision to ack or nack this 
patch because he has a better understanding of that expectation from users 
who use hugetlb pages.