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Date:   Mon, 7 Jun 2021 16:52:41 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Nicholas Piggin <npiggin@gmail.com>
Cc:     Randy Dunlap <rdunlap@infradead.org>, linux-kernel@vger.kernel.org,
        linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        linux-mm@kvack.org, Anton Blanchard <anton@ozlabs.org>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: [PATCH v4 4/4] powerpc/64s: enable MMU_LAZY_TLB_SHOOTDOWN
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On Sat,  5 Jun 2021 11:42:16 +1000 Nicholas Piggin <npiggin@gmail.com> wrote:

> On a 16-socket 192-core POWER8 system, a context switching benchmark
> with as many software threads as CPUs (so each switch will go in and
> out of idle), upstream can achieve a rate of about 1 million context
> switches per second. After this patch it goes up to 118 million.

Nice.  Do we have a feel for the benefit on any real-world workloads?

Could any other architectures benefit from these changes?