Load at 1.00 on SMP machine

myfreebsd at cox.net myfreebsd at cox.net
Mon Nov 21 15:19:25 GMT 2005

>i got a Problem on my dual XEON 3.06 GhZ machine, 2GB of >RAM, FreeBSD
>I got "option SMP" in the kernel config and >"machdep.hlt_logical_cpus=1" in
>There are just 20 processes running (typical ones like >getty and stuff) and
>the load of this machine is at 1.xx. There is no bgfsck and >other stuff.

>So, i built a new kernel without "option SMP", rebooted, >and the load was
>at 0.0x. But only one CPU was used (detected).

>So, what could bei the Problem?
>Well, the machine shows me 4 CPUs, HTT is not enabled via >/boot/loader.conf
>and "machdep.hyperthreading_allowed". So, how to disable >HTT? Maybe this is
>the problem of the high load?

Why are you setting machdep.hlt_logical_cpus=1? My understanding, this would turn off one of the cpus. It should be set to 0 to have both cpus going. Also it is set in sysctl.conf not loader.conf, at least, that is how I have it. 

I am also curious how machdep.hyperthreading_allowed works. I run 6 so I believe it is turned on by default. Is this correct? Also if it is a solo cpu with HTT, do you need option SMP and machdep.hlt_logical_cpus=0 set or not with machdep.hyperthreading_allowed on?


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