the first thing to check, does latest x86.git work fine:
http://people.redhat.com/mingo/x86.git/README
? We've got fixes queued up - in particular one could result in 'slow'
systems by virtue of denying an ioremap():
Subject: revert: "x86: ioremap(), extend check to all RAM pages"
maybe the bisection went haywire.
Or the secondary core booted up in such a sucky way that it causes such
massive slowdowns? Perhaps we are flooding the system with local APIC
timer interrupts or other interrupts?
Ingo
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