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Date:   Wed, 8 Jun 2022 10:16:12 -0400
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     Ying Huang <ying.huang@intel.com>
Cc:     linux-mm@kvack.org, Hao Wang <haowang3@fb.com>,
        Abhishek Dhanotia <abhishekd@fb.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Yang Shi <yang.shi@linux.alibaba.com>,
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        linux-kernel@vger.kernel.org, kernel-team@fb.com,
        Hasan Al Maruf <hasanalmaruf@fb.com>,
        Wei Xu <weixugc@google.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
        Yang Shi <shy828301@gmail.com>
Subject: Re: [PATCH] mm: mempolicy: N:M interleave policy for tiered memory
 nodes
Message-ID: <YqCvLM/ZMupRPpXP@cmpxchg.org>
References: <20220607171949.85796-1-hannes@cmpxchg.org>
 <dece66a05bb63a04706d25ca86f75bfc875c27fd.camel@intel.com>
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On Wed, Jun 08, 2022 at 12:19:52PM +0800, Ying Huang wrote:
> In general, I think the use case is valid.

Excellent!

> But we are changing memory tiering now, including
> 
> - make memory tiering explict
> 
> - support more than 2 tiers
> 
> - expose memory tiering via sysfs
> 
> Details can be found int the following threads,
> 
> https://lore.kernel.org/lkml/CAAPL-u9Wv+nH1VOZTj=9p9S70Y3Qz3+63EkqncRDdHfubsrjfw@mail.gmail.com/
> https://lore.kernel.org/lkml/20220603134237.131362-1-aneesh.kumar@linux.ibm.com/
> 
> With these changes, we may need to revise your implementation.  For
> example, put interleave knobs in memory tier sysfs interface, support
> more than 2 tiers, etc.

Yeah, I was expecting the interface to be the main sticking point ;)
I'll rebase this patch as the mentioned discussions find consensus.

Thanks!