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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: BC81A140004 X-Stat-Signature: q6xa8djr7qixioqhukrht67t3jppmeyq X-HE-Tag: 1740755968-358333 X-HE-Meta: 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 aldLyajx 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 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: List-Subscribe: List-Unsubscribe: On 28.02.25 16:10, David Hildenbrand wrote: > On 28.02.25 15:59, Sean Christopherson wrote: >> On Fri, Feb 28, 2025, David Hildenbrand wrote: >>> On 28.02.25 06:17, Linus Torvalds wrote: >>>> On Thu, 27 Feb 2025 at 19:03, Mathieu Desnoyers >>>> wrote: >>>>> >>>>> I'd be fine with SKSM replacing KSM entirely. However, I don't >>>>> think we should try to re-implement the existing KSM userspace ABIs >>>>> over SKSM. >>>> >>>> No, absolutely. The only point (for me) for your new synchronous one >>>> would be if it replaced the kernel thread async scanning, which would >>>> make the old user space interface basically pointless. >>>> >>>> But I don't actually know who uses KSM right now. My reaction really >>>> comes from a "it's not nice code in the kernel", not from any actual >>>> knowledge of the users. >>>> >>>> Maybe it works really well in some cloud VM environment, and we're >>>> stuck with it forever. >>> >>> Exactly that; and besides the VM use-case, lately people stated using it in >>> the context of interpreters (IIRC inside Meta) quite successfully as well. >> >> Does Red Hat (or any other KVM supporters) actually recommend using KSM for VMs >> in cloud environments? > > Private clouds yes, that's where it is most commonly used for. I would > assume that nobody for forgot to complete that sentence: "... nobody really should be using that in public clouds." -- Cheers, David / dhildenb