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dmarc=pass (policy=none) header.from=ibm.com X-HE-Tag: 1654676481-644970 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 6/8/22 12:29 PM, Ying Huang wrote: > On Fri, 2022-06-03 at 19:12 +0530, Aneesh Kumar K.V wrote: >> This patch adds the special string "none" as a supported memtier value >> that we can use to remove a specific node from being using as demotion target. >> >> For ex: >> :/sys/devices/system/node/node1# cat memtier >> 1 >> :/sys/devices/system/node/node1# cat ../../memtier/memtier1/nodelist >> 1-3 >> :/sys/devices/system/node/node1# echo none > memtier >> :/sys/devices/system/node/node1# >> :/sys/devices/system/node/node1# cat memtier >> :/sys/devices/system/node/node1# cat ../../memtier/memtier1/nodelist >> 2-3 >> :/sys/devices/system/node/node1# > > Do you have a practical use case for this? What kind of memory node > needs to be removed from memory tiers demotion/promotion? > This came up in our internal discussion. It was mentioned that there is a need to skip some slow memory nodes from participating in demotion. -aneesh