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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ... >> == Open Issues == >> >> * For cpusets and memory policies that restrict allocations >> to PMEM, is it OK to demote to PMEM? Do we need a cgroup- >> level API to opt-in or opt-out of these migrations? > > I'm wondering if such usecases, which don't want to have memory > allocate on pmem, will allow memory swapped out or reclaimed? If swap > is allowed then I failed to see why migrating to pmem should be > disallowed. If swap is not allowed, they should call mlock, then the > memory won't be migrated to pmem as well. Agreed. I have a hard time imagining there are a lot of folks that can tolerate the massive overhead from swapping, but can't tolerate the much smaller overhead of going to pmem instead of DRAM.