Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261604AbVEJKxp (ORCPT ); Tue, 10 May 2005 06:53:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261606AbVEJKxp (ORCPT ); Tue, 10 May 2005 06:53:45 -0400 Received: from mail.aei.ca ([206.123.6.14]:46039 "EHLO aeimail.aei.ca") by vger.kernel.org with ESMTP id S261604AbVEJKxm (ORCPT ); Tue, 10 May 2005 06:53:42 -0400 From: Ed Tomlinson Organization: me To: Bernd Paysan Subject: Re: [suse-amd64] False "lost ticks" on dual-Opteron system (=> timer twice as fast) Date: Tue, 10 May 2005 06:53:49 -0400 User-Agent: KMail/1.7.2 Cc: suse-amd64@suse.com, Andi Kleen , linux-kernel@vger.kernel.org References: <200505081445.26663.bernd.paysan@gmx.de> <200505091253.21252.bernd.paysan@gmx.de> <200505091517.30555.bernd.paysan@gmx.de> In-Reply-To: <200505091517.30555.bernd.paysan@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200505100653.50775.tomlins@cam.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2212 Lines: 52 On Monday 09 May 2005 09:17, Bernd Paysan wrote: > On Monday 09 May 2005 12:53, Bernd Paysan wrote: > > On Sunday 08 May 2005 15:40, Andi Kleen wrote: > > > Your system should be using the HPET timer to work exactly around > > > this. AMD 8000 has HPET. Can you post a boot.log? > > > > Ok, boot.log attached. The only entry with hpet seems to indicate some > > problems. > > I went through the BIOS setup, and found a disabled feature "ACPI 2.0", > which I enabled. Now Linux finds the HPET timer. > > # grep -i hpet boot.log > ACPI: HPET (v001 A M I OEMHPET 0x04000518 MSFT 0x00000097) @ > 0x00000000e8ff3c30 > ACPI: HPET id: 0x102282a0 base: 0xfec01000 > time.c: Using 14.318180 MHz HPET timer.> > time.c: Using HPET based timekeeping. > hpet0: at MMIO 0xfec01000, IRQs 2, 8, 0 > hpet0: 69ns tick, 3 32-bit timers > hpet_acpi_add: no address or irqs in _CRS > > and everything appears to work (though there's still no designated CPU to > handle the timer interrupts). xntpd syncs quickly, I'm happy (so far ;-). > > So that explains why nobody sees this problem. But the TSC-based fallback > timekeeping is still broken on SMP systems with PowerNow and distributed > IRQ handling, which both together seem to be rare enough ;-). Maybe on UP too: May 8 18:50:25 grover kernel: [143640.507170] Attached scsi removable disk sda at scsi5, channel 0, id 0, lun 0 May 8 18:50:25 grover kernel: [143640.520422] rtc: lost some interrupts at 1024Hz. May 8 18:50:25 grover kernel: [143640.554134] Attached scsi generic sg0 at scsi5, channel 0, id 0, lun 0, type 0 May 8 18:50:25 grover kernel: [143640.567693] rtc: lost some interrupts at 1024Hz. May 8 18:50:25 grover kernel: [143640.596402] usb-storage: device scan complete This from 12-rc3-mm3, UP x86_64 with powernow active. It might be that the message is OK here since I do not see a fast clock. I mention this since powernow is active here. Should HPET be available in UP? Ed Tomlinson - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/