From owner-freebsd-smp Mon Mar 10 10: 0: 0 2003 Delivered-To: freebsd-smp@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 80CA537B401 for ; Mon, 10 Mar 2003 09:59:58 -0800 (PST) Received: from mail.speakeasy.net (mail15.speakeasy.net [216.254.0.215]) by mx1.FreeBSD.org (Postfix) with ESMTP id B774143F3F for ; Mon, 10 Mar 2003 09:59:57 -0800 (PST) (envelope-from jhb@FreeBSD.org) Received: (qmail 646 invoked from network); 10 Mar 2003 18:00:01 -0000 Received: from unknown (HELO server.baldwin.cx) ([216.27.160.63]) (envelope-sender ) by mail15.speakeasy.net (qmail-ldap-1.03) with DES-CBC3-SHA encrypted SMTP for ; 10 Mar 2003 18:00:01 -0000 Received: from laptop.baldwin.cx (gw1.twc.weather.com [216.133.140.1]) by server.baldwin.cx (8.12.6/8.12.6) with ESMTP id h2AHuMhT065523; Mon, 10 Mar 2003 12:56:22 -0500 (EST) (envelope-from jhb@FreeBSD.org) Message-ID: X-Mailer: XFMail 1.5.2 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <20030308121852.GA25380@murmeldjur.it.su.se> Date: Mon, 10 Mar 2003 13:00:13 -0500 (EST) From: John Baldwin To: Richard Nyberg Subject: RE: hyperthreading randomness Cc: freebsd-smp@freebsd.org Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On 08-Mar-2003 Richard Nyberg wrote: > I have a Dell Precision 450 with 2 xeon CPU:s. > The weird thing is that it randomly boots up > with either 2 or 4 CPUs on the same 4-STABLE kernel. > 2 more often than 4. It seems a bit unpredictable :( Hmm, I have no idea about that one. Hmm, it seems to be a "feature" of the BIOS perhaps. It seems that it may be listing the second CPU with an APIC ID of 3 (it's second core) instead of 2 (it's first core) in which case the HTT code sees that something is not right and doesn't start up any extra processors. > CPU: Intel(R) Xeon(TM) CPU 2.66GHz (2657.82-MHz 686-class CPU) > Origin = "GenuineIntel" Id = 0xf27 Stepping = 7 > > Features=0xbfebfbff H,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE> > Hyperthreading: 2 logical CPUs > > Diff of dmesg with 2 and 4 CPUs. > > --- /tmp/dmesg.old Sat Mar 8 12:10:33 2003 > +++ /var/run/dmesg.boot Sat Mar 8 11:57:38 2003 > @@ -19,7 +19,9 @@ > Programming 24 pins in IOAPIC #2 > FreeBSD/SMP: Multiprocessor motherboard > cpu0 (BSP): apic id: 0, version: 0x00050014, at 0xfee00000 > - cpu1 (AP): apic id: 3, version: 0x00050014, at 0xfee00000 > + cpu1 (AP): apic id: 1, version: 0x00050014, at 0xfee00000 > + cpu2 (AP): apic id: 2, version: 0x00050014, at 0xfee00000 > + cpu3 (AP): apic id: 3, version: 0x00050014, at 0xfee00000 > io0 (APIC): apic id: 4, version: 0x00178020, at 0xfec00000 > io1 (APIC): apic id: 5, version: 0x00178020, at 0xfec80000 > io2 (APIC): apic id: 6, version: 0x00178020, at 0xfec80800 > @@ -103,6 +105,8 @@ > APIC_IO: Testing 8254 interrupt delivery > APIC_IO: routing 8254 via IOAPIC #0 intpin 2 > SMP: AP CPU #1 Launched! > +SMP: AP CPU #3 Launched! > +SMP: AP CPU #2 Launched! > ad0: 38146MB [77504/16/63] at ata0-master UDMA100 > acd0: DVD-ROM at ata1-master UDMA33 > acd1: CD-RW at ata1-slave UDMA33 > > -Richard > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-smp" in the body of the message -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message