On Thu, 1 Mar 2007 21:11:58 -0800 (PST) Linus Torvalds <[EMAIL PROTECTED]> wrote:
> The whole DRAM power story is a bedtime story for gullible children. Don't > fall for it. It's not realistic. The hardware support for it DOES NOT > EXIST today, and probably won't for several years. And the real fix is > elsewhere anyway (ie people will have to do a FBDIMM-2 interface, which > is against the whole point of FBDIMM in the first place, but that's what > you get when you ignore power in the first version!). > At first, we have memory hot-add now. So I want to implement hot-removing hot-added memory, at least. (in this case, we don't have to write invasive patches to memory-init-core.) Our(Fujtisu's) product, ia64-NUMA server, has a feature to offline memory. It supports dynamic reconfigraion of nodes, node-hoplug. But there is no *shipped* firmware for hotplug yet. RHEL4 couldn't boot on such hotplug-supported-firmware...so firmware-team were not in hurry. It will be shipped after RHEL5 comes. IMHO, a firmware which supports memory-hot-add are ready to support memory-hot-remove if OS can handle it. Note: I heard embeded people often designs their own memory-power-off control on embeded Linux. (but it never seems to be posted to the list.) But I don't know they are interested in generic memory hotremove or not. Thanks, -Kame - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
