Re: [patch 1/2] x86: add numa=possible command line option

David Rientjes
2010-11-21T21:46:16Z

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On Sun, 21 Nov 2010, Américo Wang wrote:

> I am not sure how much value of making this dynamic,
> for CPU, we do this at compile time, i.e. NR_CPUS,
> so how about NR_NODES?
>

This is outside the scope of node hotplug emulation, it needs to be built
on top of whatever the kernel implements.

> Also, numa=possible= is not as clear as numa=max=, for me at least.
>

I like name, but it requires that you know how many nodes that system
already has. In other words, numa=possible=4 allows you to specify that 4
additional nodes will be possible, but initially offline, for this or
other purposes. numa=max=4 would be no-op if the system actually had 4
nodes.

I chose numa=possible over numa=additional because it is more clearly tied
to node_possible_map, which is the only thing it modifies.