Re: The machdep.hyperthreading_allowed & ULE weirdness in 7.1

On Mon, 23 Feb 2009, Robert Watson wrote:

It's not quite that simple -- in a world of device drivers pinning threads to CPUs for workload distribution, callout threads and sched_bind()/sched_pin() for crypto load distribution, etc, you need a whole infrastructure for software-disabled CPUs. Disabling it using the BIOS or device.hints is the only reliable way to do this right now. Changing the architecture of the kernel to disable CPU cores after boot is a significant investment of work,

^^^^ s/disable/desirable/

Robert N M Watson
Computer Laboratory
University of Cambridge
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