machdep.hlt_logical_cpus missing in 4.9-Release?
jhb at FreeBSD.org
Thu Jan 15 10:42:29 PST 2004
On Thursday 15 January 2004 05:48 am, Hall J D (ISeLS) wrote:
> I've recently installed 4.9-Release (from the ISOs) on a twin Xeon system
> and compiled a generic SMP kernel (GENERIC with SMP and APIC_IO enabled).
> The problem I'm having is the system is using the logical HyperThreading
> CPUs even though I don't want it to.
> The errata for 4.9-Release says that the logical CPUs are prevented from
> executing user processes by default, they are not on my system. It also
> says you can control this behaviour by change the value of the
> machdep.hlt_logical_cpus sysctl(8) variable. My sysctl doesn't seem to know
> about this variable.
> I've checked the archives and someone else had this problem back in
> November but I can't see any replies other than "machdep.hlt_logical_cpus
> should be there".
> Can anyone offer some advise please.
Well, you can do 'sysctl machdep.hlt_cpus=10 to get the same effect to turn
off CPU's 1and 3. I am not sure why you are not getting the sysctls. Are
you familiar with C?
John Baldwin <jhb at FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve" = http://www.FreeBSD.org
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