telling real from HTT CPUs under xen?

[Thor Lancelot Simon <tls%rek.tjls.com@localhost>]

I have a system with two 3.2Ghz Pentium 4 CPUs, which have HTT.

It reports CPUs with apid 0, 6, 1, 7, in that order -- both in the Xen
and the NetBSD dmesg.  Of course these are actually 4 hardware threads
on 2 physical processors.

I will only ever have two domUs on this host and want to pin each to a
different _physical_ processor.  The boot CPU is apid 0, and I suspect
that 0 and 6 are on that physical CPU while 1 and 7 are on the other; but
how can I tell?  I don't see anything relevant in any diagnostic output
I can get either from NetBSD or Xen.

-- 
Thor Lancelot Simon                                        
tls%rek.tjls.com@localhost
    "Even experienced UNIX users occasionally enter rm *.* at the UNIX
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