Date: Fri, 31 May 2013 11:27:13 -0400 From: John Baldwin <jhb@freebsd.org> To: Kostas Oikonomou <k.oikonomou@att.net> Cc: freebsd-amd64@freebsd.org Subject: Re: idle process keeping cpu 150% busy in freebsd 9.1-amd64 Message-ID: <201305311127.13846.jhb@freebsd.org> In-Reply-To: <51A8B806.5090100@att.net> References: <51A7B693.8050705@att.net> <201305310836.02815.jhb@freebsd.org> <51A8B806.5090100@att.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Friday, May 31, 2013 10:47:34 am Kostas Oikonomou wrote: > Thanks very much for the reply. > > Being new to FreeBSD, this still seems weird to me. (My > background is Solaris.) > > On both machines, the core that's running at 150% in the > case of the HP machine, and at 400% in the case > of the Dell laptop, is causing the fans to come on. Would > you call that "idle"? I'm worried that the cores will > eventually be damaged. Do you have deeper Cx states enabled? By default FreeBSD will only enter C1. Try setting 'performance_cx_lowest=LOW' in /etc/rc.conf and either rebooting or running '/etc/rc.d/power_profile start' to see if that helps. You can see which Cx states are being used by running 'sysctl dev.cpu | grep cx_'. For example: dev.cpu.0.cx_supported: C1/3 C2/59 C3/93 dev.cpu.0.cx_lowest: C1 dev.cpu.0.cx_usage: 100.00% 0.00% 0.00% last 324us dev.cpu.1.cx_supported: C1/3 C2/59 C3/93 dev.cpu.1.cx_lowest: C1 dev.cpu.1.cx_usage: 100.00% 0.00% 0.00% last 300us dev.cpu.2.cx_supported: C1/3 C2/59 C3/93 dev.cpu.2.cx_lowest: C1 dev.cpu.2.cx_usage: 100.00% 0.00% 0.00% last 192us dev.cpu.3.cx_supported: C1/3 C2/59 C3/93 dev.cpu.3.cx_lowest: C1 dev.cpu.3.cx_usage: 100.00% 0.00% 0.00% last 157us This is on a machine with the default setup. After changing it to use the lowest setting: dev.cpu.0.cx_supported: C1/3 C2/59 C3/93 dev.cpu.0.cx_lowest: C3 dev.cpu.0.cx_usage: 5.84% 92.86% 1.28% last 145us dev.cpu.1.cx_supported: C1/3 C2/59 C3/93 dev.cpu.1.cx_lowest: C3 dev.cpu.1.cx_usage: 0.99% 94.92% 4.08% last 293us dev.cpu.2.cx_supported: C1/3 C2/59 C3/93 dev.cpu.2.cx_lowest: C3 dev.cpu.2.cx_usage: 0.45% 88.50% 11.04% last 174us dev.cpu.3.cx_supported: C1/3 C2/59 C3/93 dev.cpu.3.cx_lowest: C3 dev.cpu.3.cx_usage: 6.40% 86.89% 6.69% last 203us Another option is to run powerd which will throttle your CPUs down to lower clock speeds when they are idle. You can enable this by setting powerd_enable="YES" in /etc/rc.conf and running '/etc/rc.d/powerd start'. -- John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201305311127.13846.jhb>