I too have experienced this problem with -current. I'm running on a Thinkpad A21p, but with a fairly out-of-date build (September 1, 2001).
This happens, I believe. because the kernel thinks the processor is running at one speed and then that speed changes to reflect different power management settings. For example, if I configure BIOS APM to clockdown the processor on battery and run full-throttle on AC power. My clock runs smoothly on battery (the condition I booted in), but when I engage the AC the clock runs a few times faster than normal. I can control this condition simply adding and removing AC power and having the BIOS APM react. It is clear: the processor speed is not held constant and this produces the behavior you mention. Some data points: Right after boot ntptimeset reports: Your clock is off by -4.4654581 seconds. (18.104.22.168) [48/47] Some minutes later: Your clock is off by -1710.9709441 seconds. (22.214.171.124) [37/36] Anyways, my dmesg is attached. -Jon
Copyright (c) 1992-2001 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 5.0-CURRENT #1: Sat Sep 1 01:18:52 PDT 2001 [EMAIL PROTECTED]:/usr/obj/usr/src/sys/PHILEMON Timecounter "i8254" frequency 1193182 Hz Timecounter "TSC" frequency 846865184 Hz CPU: Pentium III/Pentium III Xeon/Celeron (846.87-MHz 686-class CPU) Origin = "GenuineIntel" Id = 0x686 Stepping = 6 Features=0x383f9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE> real memory = 134152192 (131008K bytes) avail memory = 125894656 (122944K bytes) Preloaded elf kernel "kernel" at 0xc0490000. Preloaded userconfig_script "/boot/kernel.conf" at 0xc049009c. Pentium Pro MTRR support enabled Using $PIR table, 11 entries at 0xc00fdee0 npx0: <math processor> on motherboard npx0: INT 16 interface pcib0: <Intel 82443BX (440 BX) host to PCI bridge> at pcibus 0 on motherboard pci0: <PCI bus> on pcib0 pcib1: <PCI-PCI bridge> at device 1.0 on pci0 pci1: <PCI bus> on pcib1 pci1: <display, VGA> at 0.0 (no driver attached) pcic0: <TI PCI-1450 PCI-CardBus Bridge> mem 0x50000000-0x50000fff irq 11 at device 2.0 on pci0 pcic0: TI12XX PCI Config Reg: [ring enable][speaker enable][pwr save][FUNC pci int + CSC serial isa irq] pccard0: <PC Card bus (classic)> on pcic0 pcic1: <TI PCI-1450 PCI-CardBus Bridge> mem 0x50100000-0x50100fff irq 11 at device 2.1 on pci0 pcic1: TI12XX PCI Config Reg: [ring enable][speaker enable][pwr save][FUNC pci int + CSC serial isa irq] pccard1: <PC Card bus (classic)> on pcic1 fxp0: <Intel Pro 10/100B/100+ Ethernet> port 0x1800-0x183f mem 0xf0100000-0xf011ffff,0xf0120000-0xf0120fff irq 11 at device 3.0 on pci0 fxp0: Ethernet address 00:10:a4:8e:87:33 inphy0: <i82555 10/100 media interface> on miibus0 inphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto pci0: <simple comms, UART> at 3.1 (no driver attached) csa0: <CS4280/CS4614/CS4622/CS4624/CS4630> mem 0xf0000000-0xf00fffff,0xf0122000-0xf0122fff irq 11 at device 5.0 on pci0 csa: card is Thinkpad 600X/A20/T20 pcm0: <CS461x PCM Audio> on csa0 isab0: <PCI-ISA bridge> at device 7.0 on pci0 isa0: <ISA bus> on isab0 atapci0: <Intel PIIX4 ATA33 controller> port 0x1850-0x185f at device 7.1 on pci0 ata0: at 0x1f0 irq 14 on atapci0 ata1: at 0x170 irq 15 on atapci0 uhci0: <Intel 82371AB/EB (PIIX4) USB controller> port 0x1860-0x187f irq 11 at device 7.2 on pci0 usb0: <Intel 82371AB/EB (PIIX4) USB controller> on uhci0 usb0: USB revision 1.0 uhub0: Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1 uhub0: 2 ports with 2 removable, self powered pci0: <bridge, PCI-unknown> at 7.3 (no driver attached) orm0: <Option ROMs> at iomem 0xc0000-0xcffff,0xd0000-0xd17ff,0xe0000-0xeffff on isa0 atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0 atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0 kbd0 at atkbd0 psm0: <PS/2 Mouse> irq 12 on atkbdc0 psm0: model Generic PS/2 mouse, device ID 0 fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0 fdc0: FIFO enabled, 8 bytes threshold fd0: <1440-KB 3.5" drive> on fdc0 drive 0 pmtimer0 on isa0 ppc0: <Parallel port> at port 0x3bc-0x3c3 irq 7 on isa0 ppc0: Generic chipset (NIBBLE-only) in COMPATIBLE mode plip0: <PLIP network interface> on ppbus0 lpt0: <Printer> on ppbus0 lpt0: Interrupt-driven port ppi0: <Parallel I/O> on ppbus0 sc0: <System console> at flags 0x100 on isa0 sc0: VGA <16 virtual consoles, flags=0x300> sio0: configured irq 4 not in bitmap of probed irqs 0 sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0 sio0: type 8250 sio1: configured irq 3 not in bitmap of probed irqs 0 vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0 unknown: <PNP0303> can't assign resources unknown: <IBM0071> can't assign resources unknown: <IBM3780> can't assign resources unknown: <PNP0680> can't assign resources unknown: <PNP0680> can't assign resources unknown: <PNP0400> can't assign resources unknown: <PNP0700> can't assign resources IP packet filtering initialized, divert enabled, rule-based forwarding enabled, default to accept, logging limited to 100 packets/entry by default IP Filter: v3.4.20 initialized. Default = block all, Logging = enabled ata1-slave: ata_command: timeout waiting for intr ata1-slave: identify failed ad0: 30520MB <IBM-DJSA-232> [66144/15/63] at ata0-master UDMA33 acd0: DVD-ROM <HITACHI DVD-ROM GD-S200> at ata1-master PIO4 Mounting root from ufs:/dev/ad0s2a lock order reversal 1st 0xc8d1621c process lock @ /usr/src/sys/vm/vm_glue.c:469 2nd 0xc0b30ec0 lockmgr interlock @ /usr/src/sys/kern/kern_lock.c:239