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Subject: Re: MAXCPU preparations
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On 28 Sep 2010, at 19:40, Sean Bruno wrote:

>> If you go fully dynamic you should use mp_maxid + 1 rather than =
maxcpus.
>=20
> I assume that mp_maxid is the new kern.smp.maxcpus?  Can you inject =
some
> history here so I can understand why one is "better" than the other?

So, unlike maxcpus, mp_maxid is in theory susceptible to races in a =
brave new world in which we support hotplug CPUs -- a brave new world =
we're not yet ready for, however. If you do use mp_maxid, be aware you =
need to add one to get the size of the array -- maxcpus is the number of =
CPUs that can be used, whereas mp_maxid is the highest CPU ID (counting =
from 0) that is used.

Robert=