Bug 18798

Summary:	microuptime() went backwards
Product:	Base System	Reporter:	jkolb <jkolb>
Component:	kern	Assignee:	freebsd-bugs (Nobody) <bugs>
Status:	Closed FIXED
Severity:	Affects Only Me
Priority:	Normal
Version:	Unspecified
Hardware:	Any
OS:	Any

Description jkolb 2000-05-24 22:00:01 UTC

Infinite and continuous "microuptime() went backwards" log messages.

Fix: 

Reboot?
How-To-Repeat: Not sure it has seemed to happen the most when using /stand/sysinstall
to install a package or during the install itself. It is not to my
knowledge reproducible.

Comment 1 Poul-Henning Kamp freebsd_committer

2000-06-10 20:17:24 UTC

State Changed
From-To: open->feedback

Please try with a kernel without APM support. 
please include dmesg & sysctl kern.timecounter output.

Comment 2 Valentin Nechayev 2000-06-19 14:11:16 UTC

phk wrote:

> State-Changed-From-To: open->feedback
> State-Changed-By: phk
> State-Changed-When: Sat Jun 10 12:17:24 PDT 2000
> State-Changed-Why:
> Please try with a kernel without APM support.
> please include dmesg & sysctl kern.timecounter output.

I have seen it at our Alpha box:

==={
Copyright (c) 1992-2000 The FreeBSD Project.
Copyright (c) 1982, 1986, 1989, 1991, 1993
        The Regents of the University of California. All rights reserved.
FreeBSD 4.0-STABLE #0: Tue May  2 23:54:37 EEST 2000
    root@aleph.carrier.kiev.ua:/var/src/sys/compile/ALEPH
EB164
Digital AlphaPC 164SX 533 MHz, 531MHz
8192 byte page size, 1 processor.
CPU: PCA56 (21164PC) major=9 minor=2 extensions=0x1<BWX>
OSF PAL rev: 0x1000600020116
real memory  = 132268032 (129168K bytes)
avail memory = 124796928 (121872K bytes)
Preloaded elf kernel "kernel" at 0xfffffc0000586000.
md0: Malloc disk
cia0: Pyxis, pass 1
cia0: extended capabilities: 1<BWEN>
pcib0: <2117x PCI host bus adapter> on cia0
pci0: <PCI bus> on pcib0
dc0: <Intel 21143 10/100BaseTX> port 0x10100-0x1017f mem 0x82072000-0x820723ff i
rq 9 at device 5.0 on pci0
dc0: interrupting at CIA irq 9
dc0: Ethernet address: 00:80:48:cd:63:0a
miibus0: <MII bus> on dc0
amphy0: <Am79C873 10/100 media interface> on miibus0
amphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
isab0: <Cypress 82C693 PCI-ISA bridge> at device 8.0 on pci0
isa0: <ISA bus> on isab0
pci0: <Cypress 82C693 ATA controller> at 8.1
pci0: <Cypress 82C693 ATA controller> at 8.2
pci0: <Cypress 82C693 ATA controller> at 8.3
sym0: <875> port 0x10000-0x100ff mem 0x82071000-0x82071fff,0x82072400-0x820724ff
 irq 8 at device 9.0 on pci0
sym0: Symbios NVRAM, ID 7, Fast-20, SE, NO parity
sym0: open drain IRQ line driver, using on-chip SRAM
sym0: SCAN AT BOOT disabled for targets 2 4 5 6 8 9 10 11 12 13 14 15.
sym0: SCAN FOR LUNS disabled for targets 2 4 5 6 8 9 10 11 12 13 14 15.
sym0: interrupting at CIA irq 8
fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0
fdc0: interrupting at ISA irq 6
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
atkbd0: interrupting at ISA irq 1
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
sc0: <System console> on isa0
sc0: VGA <16 virtual consoles, flags=0x200>
mcclock0: <MC146818A real time clock> at port 0x70-0x71 on isa0
sio0 at port 0x3f8-0x3ff irq 4 on isa0
sio0: type 16550A
sio0: interrupting at ISA irq 4
sio1: reserved for low-level i/o
Timecounter "alpha"  frequency 533176256 Hz
Waiting 5 seconds for SCSI devices to settle
(noperiph:sym0:0:-1:-1): SCSI BUS reset delivered.
Mounting root from ufs:/dev/da0a
da0 at sym0 bus 0 target 0 lun 0
da0: <IBM DCAS-34330W S61A> Fixed Direct Access SCSI-2 device
da0: 40.000MB/s transfers (20.000MHz, offset 15, 16bit)
da0: 4134MB (8467200 512 byte sectors: 255H 63S/T 527C)
WARNING: / was not properly dismounted
dc0: TX underrun -- increasing TX threshold
dc0: TX underrun -- increasing TX threshold
dc0: TX underrun -- increasing TX threshold
dc0: TX underrun -- using store and forward mode
microuptime() went backwards (1119617.816600 -> 1119617,321192)
microuptime() went backwards (1119617.816600 -> 1119617,321813)
microuptime() went backwards (1119617.816600 -> 1119617,420793)
microuptime() went backwards (1119617.816600 -> 1119617,520401)
microuptime() went backwards (1119617.816600 -> 1119617,620007)
microuptime() went backwards (1119617.816600 -> 1119617,664929)
microuptime() went backwards (1119617.816600 -> 1119617,665738)
microuptime() went backwards (1119617.816600 -> 1119617,665738)
microuptime() went backwards (1119617.816600 -> 1119617,719616)
pid 208 (squid), uid 65530: exited on signal 6
Waiting (max 60 seconds) for system process `bufdaemon' to stop...stopped
Waiting (max 60 seconds) for system process `syncer' to stop...stopped

syncing disks...
done
Uptime: 26d8h2m58s
Rebooting...
Copyright (c) 1992-2000 The FreeBSD Project.
Copyright (c) 1982, 1986, 1989, 1991, 1993
        The Regents of the University of California. All rights reserved.
FreeBSD 4.0-STABLE #0: Tue May  2 23:54:37 EEST 2000
    root@aleph.carrier.kiev.ua:/var/src/sys/compile/ALEPH
===}

Also:

netch@aleph:~>sysctl kern.timecounter
kern.timecounter.method: 0
kern.timecounter.hardware: alpha
netch@aleph:~>


--
NVA

Comment 3 Poul-Henning Kamp 2000-06-19 14:20:21 UTC

Alphas are special in two ways:  The CPU clock is not quartz xtal
derived, but rather generated by a SAW device which has really
good applications as thermometer.  This brings the other surprise:
SMP alpha systems have asynchronous CPU clocks.

I have no suggestions at this time.

--
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD coreteam member | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

Comment 4 Poul-Henning Kamp freebsd_committer

2001-05-29 10:22:55 UTC

State Changed
From-To: feedback->closed

Known issue.