Date: Tue, 14 Mar 2006 10:41:17 -0500 From: John Baldwin <jhb@freebsd.org> To: freebsd-amd64@freebsd.org Subject: Re: How is hyperthreading handled on amd64? Message-ID: <200603141041.19069.jhb@freebsd.org> In-Reply-To: <20060314093614.e5247e95.wmoran@collaborativefusion.com> References: <20060313085431.0eb059d9.wmoran@collaborativefusion.com> <200603131532.53869.jhb@freebsd.org> <20060314093614.e5247e95.wmoran@collaborativefusion.com>
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On Tuesday 14 March 2006 09:36, Bill Moran wrote: > On Mon, 13 Mar 2006 15:32:51 -0500 > John Baldwin <jhb@freebsd.org> wrote: > > > On Monday 13 March 2006 15:04, Bill Moran wrote: > > > On Mon, 13 Mar 2006 14:06:34 -0500 > > > John Baldwin <jhb@freebsd.org> wrote: > > > > > > [...] > > > > > I can't argue that the boot messages don't seem to show anything to > > > > > indicate that a second logical CPU was found. > > > > > > > > Grab the dmesg from /var/run/dmesg.boot rather than /var/log/messages > > > > please. > > > > > > Copyright (c) 1992-2005 The FreeBSD Project. > > > Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994 > > > The Regents of the University of California. All rights reserved. > > > FreeBSD 6.0-RELEASE-p5 #1: Fri Mar 10 16:57:56 EST 2006 > > > root@:/usr/obj/usr/src/sys/DB64 > > > Timecounter "i8254" frequency 1193182 Hz quality 0 > > > CPU: Intel(R) Xeon(TM) CPU 3.00GHz (2992.71-MHz K8-class CPU) > > > Origin = "GenuineIntel" Id = 0xf41 Stepping = 1 > > > Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE> > > > Features2=0x641d<SSE3,RSVD2,MON,DS_CPL,CNTX-ID,CX16,<b14>> > > > AMD Features=0x20000800<SYSCALL,LM> > > > Hyperthreading: 2 logical CPUs > > > real memory = 2147221504 (2047 MB) > > > avail memory = 2066378752 (1970 MB) > > > ACPI APIC Table: <DELL PE BKC > > > > FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs > > > cpu0 (BSP): APIC ID: 0 > > > cpu1 (AP): APIC ID: 1 > > > > This is a dmesg from an SMP kernel this time. :) > > > > Can you provide the output from 'sysctl machdep'? > > machdep.hlt_cpus: 2 > machdep.hlt_logical_cpus: 0 > machdep.logical_cpus_mask: 2 > machdep.hyperthreading_allowed: 0 Ok, the mask is right (CPU 1 is marked as a hyperthread), and it's marked as disabled in hlt_cpus. I think I know what is happening. Can you update to the latest RELENG_6 and see if the issue still occurs. -- John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.orghome | help
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