From mboxrd@z Thu Jan 1 00:00:00 1970 From: christoffer.dall@linaro.org (Christoffer Dall) Date: Tue, 29 Jul 2014 15:33:10 +0200 Subject: [PATCH 19/19] Documentation: ACPI for ARM64 In-Reply-To: <351673188.FxXsM7MvdA@wuerfel> References: <1406206825-15590-1-git-send-email-hanjun.guo@linaro.org> <20140729112824.GM2576@leverpostej> <351673188.FxXsM7MvdA@wuerfel> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 29 July 2014 14:52, Arnd Bergmann wrote: > On Tuesday 29 July 2014 14:37:38 Christoffer Dall wrote: >> >> For reference, Red Hat's current arguing point for ACPI in VMs is >> hotplug of things like CPUs and memory for very large VMs, but I >> haven't thought too carefully about this just yet, as I don't have a >> 100+ core ARM 64-bit hardware lying around... > > I thought you could run guests with more virtual CPUs that you have > physical CPUs on the host. > you can, my sentence was meant to be a bit tongue-in-cheek, running 100 VCPUs on the Foundation Model (which is the only thing I have on my desk as of now) is not very useful, so I just don't care at this point. Let me see or give me access to something with at least 8 physical cores before I start caring (with my community hat on, as a Linaro employee I may be told to care). > Regarding CPU and memory hotplug, don't we already have PSCI and > xen-balloon/virtio-balloon for that? > Virtio-balloon don't do anything for you wrt. CPUs, wrt. memory you have to provision it beforehand. -Christoffer