Messages in this thread |  | | Subject | Re: [PATCH v5 0/5] Add movablecore_map boot option | From | Toshi Kani <> | Date | Mon, 14 Jan 2013 17:05:01 -0700 |
| |
On Mon, 2013-01-14 at 14:34 -0800, Andrew Morton wrote: > On Mon, 14 Jan 2013 09:31:33 -0800 > "H. Peter Anvin" <hpa@zytor.com> wrote: > > > On 01/14/2013 01:15 AM, Tang Chen wrote: > > > > > > For now, users can disable this functionality by not specifying the boot option. > > > Later, we will post SRAT support, and add another option value "movablecore_map=acpi" > > > to using SRAT. > > > > > > > I still think the option "movablecore_map" is uglier than hell. "core" > > could just as easily refer to CPU cores there, but it is a memory mem. > > "movablemem" seems more appropriate. > > > > Again, without SRAT I consider this patchset to be largely useless for > > anything other than prototyping work. > > > > hm, why. Obviously SRAT support will improve things, but is it > actually unusable/unuseful with the command line configuration?
I think it is useful for prototyping and testing. I do not think it is suitable for regular users.
> Also, "But even if we can use SRAT, users still need an interface to > enable/disable this functionality if they don't want to loose their > NUMA performance. So I think, an user interface is always needed."
Yes, but such user interface could be provided through the management interface (GUI/CLI) of the platforms (or VMs). If user sets for performance, SRAT could be generated with no hot-pluggable memory. If user sets node N to be hot-removable, SRAT could be generated in such way that all memory ranges in node N are hot-pluggable.
Thanks, -Toshi
> There's also the matter of other architectures. Has any thought been > given to how (eg) powerpc would hook into here? > > And what about VMs (xen, KVM)? I wonder if there is a case for those > to implement memory hotplug. > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
|  |