Greetings All, I have installed FreeBSD 6.1 Release on a Dell 2850. I is has two Xeon CPUs. Seeing the comment in the SMP man page about hyperthreading being a problem in some situations, I added "machdep.hlt_logical_cpus=1" in /boot/loader.conf file. Upon rebooting, the system still finds four CPUs and starts all of them. I would have expected it to start only the two physical CPUs. Am I missunderstanding what machdep.hlt_logical_cpus is supposed to do? Should I even be concerned about the hyperthreading problem. This system will be an email server for a small college campus with about 2000 active accounts.
Also, the man page for SMP say that the machdep.hlt_cpus can be used to halt a specific CPU. I have not set this value, but sysctl shows it has a value of 10, even before I set the machdep.hlt_logical_cpus to 1. Why would this be the default value? I would think this would mean that one of the system CPUs is halted. But dmesg output claims it launched four CPUs. Can someone fill me in on what this all means? Thanks, Jon %dmesg Copyright (c) 1992-2006 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 6.1-RELEASE #0: Thu May 18 18:49:35 PDT 2006 [EMAIL PROTECTED]:/usr/obj/usr/src/sys/ECF Timecounter "i8254" frequency 1193182 Hz quality 0 CPU: Intel(R) Xeon(TM) CPU 3.00GHz (2992.70-MHz 686-class CPU) Origin = "GenuineIntel" Id = 0xf43 Stepping = 3 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=0x20100000<NX,LM> Logical CPUs per core: 2 real memory = 2147221504 (2047 MB) avail memory = 2100469760 (2003 MB) ACPI APIC Table: <DELL PE BKC > FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs cpu0 (BSP): APIC ID: 0 cpu1 (AP): APIC ID: 1 cpu2 (AP): APIC ID: 6 cpu3 (AP): APIC ID: 7 ioapic0: Changing APIC ID to 8 ioapic1: Changing APIC ID to 9 ioapic1: WARNING: intbase 32 != expected base 24 ioapic2: Changing APIC ID to 10 ioapic2: WARNING: intbase 64 != expected base 56 ioapic3: Changing APIC ID to 11 ioapic3: WARNING: intbase 96 != expected base 88 ioapic0 <Version 2.0> irqs 0-23 on motherboard ioapic1 <Version 2.0> irqs 32-55 on motherboard ioapic2 <Version 2.0> irqs 64-87 on motherboard ioapic3 <Version 2.0> irqs 96-119 on motherboard kbd1 at kbdmux0 acpi0: <DELL PE BKC> on motherboard acpi0: Power Button (fixed) Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000 acpi_timer0: <24-bit timer at 3.579545MHz> port 0x808-0x80b on acpi0 cpu0: <ACPI CPU> on acpi0 cpu1: <ACPI CPU> on acpi0 cpu2: <ACPI CPU> on acpi0 cpu3: <ACPI CPU> on acpi0 <...cut...> SMP: AP CPU #1 Launched! SMP: AP CPU #3 Launched! SMP: AP CPU #2 Launched! Trying to mount root from ufs:/dev/amrd0s1a Accounting enabled em0: link state changed to UP % %sysctl -a | grep -i cpu kern.threads.virtual_cpu: 4 kern.sched.ipiwakeup.onecpu: 0 kern.ccpu: 1948 kern.smp.maxcpus: 16 kern.smp.cpus: 4 debug.cpufreq.lowest: 0 debug.cpufreq.verbose: 0 debug.kdb.stop_cpus: 1 debug.PMAP1changedcpu: 0 hw.model: Intel(R) Xeon(TM) CPU 3.00GHz hw.ncpu: 4 hw.acpi.cpu.cx_supported: C1/0 hw.acpi.cpu.cx_lowest: C1 hw.acpi.cpu.cx_usage: 100.00% machdep.cpu_idle_hlt: 1 machdep.hlt_cpus: 10 machdep.hlt_logical_cpus: 1 machdep.logical_cpus_mask: 10 dev.cpu.0.%desc: ACPI CPU dev.cpu.0.%driver: cpu dev.cpu.0.%location: handle=\_PR_.CPU0 dev.cpu.0.%pnpinfo: _HID=none _UID=0 dev.cpu.0.%parent: acpi0 dev.cpu.1.%desc: ACPI CPU dev.cpu.1.%driver: cpu dev.cpu.1.%location: handle=\_PR_.CPU1 dev.cpu.1.%pnpinfo: _HID=none _UID=0 dev.cpu.1.%parent: acpi0 dev.cpu.2.%desc: ACPI CPU dev.cpu.2.%driver: cpu dev.cpu.2.%location: handle=\_PR_.CPU2 dev.cpu.2.%pnpinfo: _HID=none _UID=0 dev.cpu.2.%parent: acpi0 dev.cpu.3.%desc: ACPI CPU dev.cpu.3.%driver: cpu dev.cpu.3.%location: handle=\_PR_.CPU3 dev.cpu.3.%pnpinfo: _HID=none _UID=0 dev.cpu.3.%parent: acpi0 % _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"