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Date:   Wed, 31 Aug 2022 14:12:59 +0200
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     linux-arm-kernel@lists.infradead.org, "Yu Zhao" <yuzhao@google.com>
Cc:     "Andrew Morton" <akpm@linux-foundation.org>,
        "Andi Kleen" <ak@linux.intel.com>,
        "Aneesh Kumar" <aneesh.kumar@linux.ibm.com>,
        "Catalin Marinas" <catalin.marinas@arm.com>,
        "Dave Hansen" <dave.hansen@linux.intel.com>,
        "Hillf Danton" <hdanton@sina.com>, "Jens Axboe" <axboe@kernel.dk>,
        "Johannes Weiner" <hannes@cmpxchg.org>,
        "Jonathan Corbet" <corbet@lwn.net>,
        "Linus Torvalds" <torvalds@linux-foundation.org>,
        "Matthew Wilcox" <willy@infradead.org>,
        "Mel Gorman" <mgorman@suse.de>,
        "Michael Larabel" <Michael@michaellarabel.com>,
        "Michal Hocko" <mhocko@kernel.org>,
        "Mike Rapoport" <rppt@kernel.org>,
        "Peter Zijlstra" <peterz@infradead.org>,
        "Tejun Heo" <tj@kernel.org>, "Vlastimil Babka" <vbabka@suse.cz>,
        "Will Deacon" <will@kernel.org>,
        linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        page-reclaim@google.com
Subject: Re: OpenWrt / MIPS benchmark with MGLRU
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On Wed, Aug 31, 2022, at 6:17 AM, Yu Zhao wrote:
>
> Rational
> ========
> 1. OpenWrt is the most popular distro for WiFi routers; many of its
>    targets use big endianness [1].
> 2. 4 out of the top 5 bestselling WiFi routers in the US use MIPS [2];
>    MIPS uses software-managed TLB.
> 3. Memcached is the best available memory benchmark on OpenWrt;
>    admittedly such a use case is very limited in the real world.
>
> Hardware
> ========
> DUT: Ubiquiti EdgeRouter (ER-8) [3]

I don't know if it makes any difference to your findings, but
I would point out the test hardware is neither representative
of most devices supported by OpenWRT, nor those on the amazon
best-seller list that I see looking from Germany:

Five of the top-10 devices on that list are arm64 (little-endian,
hardware TLB walker, typically 512MB of RAM), the others are
mips32 (typically only 128MB, mostly single-core) and only
the oldest one (Archer C7) of them is big-endian. I would not
expect endianness to make any difference, but the 16x smaller
memory of typical mips devices (ath79, mt76) might.

       Arnd