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Date:   Fri, 28 Jun 2019 16:15:08 +0100
From:   Matt Fleming <matt@codeblueprint.co.uk>
To:     "Suthikulpanit, Suravee" <Suravee.Suthikulpanit@amd.com>
Cc:     Mel Gorman <mgorman@techsingularity.net>,
        Peter Zijlstra <peterz@infradead.org>,
        "Lendacky, Thomas" <Thomas.Lendacky@amd.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@alien8.de>
Subject: Re: [PATCH] sched/topology: Improve load balancing on AMD EPYC
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On Wed, 26 Jun, at 09:18:01PM, Suthikulpanit, Suravee wrote:
> 
> We use 16 to designate 1-hop latency (for different node within the same socket).
> For across-socket access, since the latency is greater, we set the latency to 32
> (twice the latency of 1-hop) not aware of the RECLAIM_DISTANCE at the time.
 
I guess the question is: Is the memory latency of a remote node 1 hop
away 1.6x the local node latency?