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Date:   Tue, 11 Jul 2023 14:11:19 -0700
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     David Hildenbrand <david@redhat.com>,
        Ryan Roberts <ryan.roberts@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Yin Fengwei <fengwei.yin@intel.com>,
        Yu Zhao <yuzhao@google.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Yang Shi <shy828301@gmail.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH v2 0/5] variable-order, large folios for anonymous memory
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On Fri, Jul 07, 2023 at 02:12:01PM +0100, Matthew Wilcox wrote:
> On Fri, Jul 07, 2023 at 01:40:53PM +0200, David Hildenbrand wrote:
> 
> > Is swapping working as expected? zswap?
> 
> Suboptimally.  Swap will split folios in order to swap them.

Wouldn't that mean if high order folios are used a lot but swap is also
used, until this is fixed you wouldn't get the expected reclaim gains
for high order folios and we'd need compaction more then?

> Somebody needs to fix that, but it should work.

As we look at shmem stuff it was on the path so something we have
considered doing. Ie, it's on our team's list of items to help with
but currently on a backburner.

  Luis