momentary system "pauses" when switching VTYs

Fri Aug 25 18:58:05 UTC 2006

Hello.

I did a stock install of 6.1-RELEASE yesterday and I noticed something
weird.  Whenever I switched the virtual console to a different screen,
it would take almost 2 whole seconds before switching.  At first I
thought it was IRQ related since it was happening during the heavy disk
activity of an install, but I noticed the same behavior after rebooting
the machine.

I csup'd to RELENG_6 as of last night and that didn't help.  One thing
I did notice is that the whole kernel seems to "pause" during the two
second switching operation-- I noticed this because I switched virtual
screens during a bg fsck and each time I switched, the ATA light would
turn off during the duration and come back on immediately after the
console switched.  This behavior is 100% repeatable for me.  I looked at
"systat -vms" and top(1) but didn't notice anything out of the ordinary.
This only seems to affect this one system;  my other machines switch
virtual screens instantly.  This happened both with GENERIC and SMP
kernels..  I'll include the latest dmesg below.  Nothing else appeared
in any logs.  I can provide a verbose dmesg if necessary.

The only thing I can think of is that I'm using kbdmux with no PS/2
keyboard attached-- but I'm using a similar USB keyboard on another
6.1-STABLE box just fine.  Any ideas?

-- Rick C. Petty

output of 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-STABLE #0: Fri Aug 25 01:16:11 CDT 2006
    root at kayla.kiwi-computer.com:/usr/obj/usr/src/sys/GENERIC
module_register: module uhub/ums already exists!
Module uhub/ums failed to register: 17
mptable_probe: MP Config Table has bad signature: 4\^C\^_
ACPI APIC Table: <Nvidia AWRDACPI>
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: AMD Sempron(tm)   2500+ (1746.83-MHz 686-class CPU)
  Origin = "AuthenticAMD"  Id = 0x681  Stepping = 1
  Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>
  AMD Features=0xc0480800<SYSCALL,MP,MMX+,3DNow+,3DNow>
real memory  = 1610547200 (1535 MB)
avail memory = 1569087488 (1496 MB)
ioapic0 <Version 1.1> irqs 0-23 on motherboard
kbd1 at kbdmux0
ath_hal: 0.9.17.2 (AR5210, AR5211, AR5212, RF5111, RF5112, RF2413, RF5413)
acpi0: <Nvidia AWRDACPI> on motherboard
acpi0: Power Button (fixed)
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x4008-0x400b on acpi0
cpu0: <ACPI CPU> on acpi0
acpi_button0: <Power Button> on acpi0
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
Correcting nForce2 C1 CPU disconnect hangs
agp0: <NVIDIA nForce2 AGP Controller> mem 0xc0000000-0xcfffffff at device 0.0 on pci0
pci0: <memory, RAM> at device 0.1 (no driver attached)
pci0: <memory, RAM> at device 0.2 (no driver attached)
pci0: <memory, RAM> at device 0.3 (no driver attached)
pci0: <memory, RAM> at device 0.4 (no driver attached)
pci0: <memory, RAM> at device 0.5 (no driver attached)
isab0: <PCI-ISA bridge> at device 1.0 on pci0
isa0: <ISA bus> on isab0
pci0: <serial bus, SMBus> at device 1.1 (no driver attached)
ohci0: <OHCI (generic) USB controller> mem 0xde086000-0xde086fff irq 20 at device 2.0 on pci0
ohci0: [GIANT-LOCKED]
usb0: OHCI version 1.0, legacy support
usb0: SMM does not respond, resetting
usb0: <OHCI (generic) USB controller> on ohci0
usb0: USB revision 1.0
uhub0: nVidia OHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 3 ports with 3 removable, self powered
ohci1: <OHCI (generic) USB controller> mem 0xde081000-0xde081fff irq 21 at device 2.1 on pci0
ohci1: [GIANT-LOCKED]
usb1: OHCI version 1.0, legacy support
usb1: SMM does not respond, resetting
usb1: <OHCI (generic) USB controller> on ohci1
usb1: USB revision 1.0
uhub1: nVidia OHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub1: 3 ports with 3 removable, self powered
ehci0: <NVIDIA nForce2 USB 2.0 controller> mem 0xde082000-0xde0820ff irq 22 at device 2.2 on pci0
ehci0: [GIANT-LOCKED]
usb2: EHCI version 1.0
usb2: companion controllers, 4 ports each: usb0 usb1
usb2: <NVIDIA nForce2 USB 2.0 controller> on ehci0
usb2: USB revision 2.0
uhub2: nVidia EHCI root hub, class 9/0, rev 2.00/1.00, addr 1
uhub2: 6 ports with 6 removable, self powered
nve0: <NVIDIA nForce MCP2 Networking Adapter> port 0xe400-0xe407 mem 0xde083000-0xde083fff irq 20 at device 4.0 on pci0
nve0: Ethernet address 00:11:2f:e4:95:b4
miibus0: <MII bus> on nve0
rlphy0: <RTL8201L 10/100 media interface> on miibus0
rlphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
nve0: Ethernet address: 00:11:2f:e4:95:b4
pci0: <multimedia, audio> at device 5.0 (no driver attached)
pcm0: <nVidia nForce2> port 0xd000-0xd0ff,0xd400-0xd47f mem 0xde087000-0xde087fff irq 22 at device 6.0 on pci0
pcm0: <Avance Logic ALC650 AC97 Codec>
pcib1: <ACPI PCI-PCI bridge> at device 8.0 on pci0
pci1: <ACPI PCI bus> on pcib1
skc0: <Marvell Gigabit Ethernet> port 0xa000-0xa0ff mem 0xdd000000-0xdd003fff irq 17 at device 4.0 on pci1
skc0: Marvell Yukon Lite Gigabit Ethernet rev. A3(0x7)
sk0: <Marvell Semiconductor, Inc. Yukon> on skc0
sk0: Ethernet address: 00:11:2f:e4:85:7e
miibus1: <MII bus> on sk0
e1000phy0: <Marvell 88E1000 Gigabit PHY> on miibus1
e1000phy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseTX-FDX, auto
pci1: <multimedia, video> at device 6.0 (no driver attached)
pci1: <multimedia> at device 6.1 (no driver attached)
atapci0: <SiI 3112 SATA150 controller> port 0xa400-0xa407,0xa800-0xa803,0xac00-0xac07,0xb000-0xb003,0xb400-0xb40f mem 0xdd004000-0xdd0041ff irq 18 at device 11.0 on pci1
ata2: <ATA channel 0> on atapci0
ata3: <ATA channel 1> on atapci0
atapci1: <nVidia nForce2 UDMA133 controller> port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0xf000-0xf00f at device 9.0 on pci0
ata0: <ATA channel 0> on atapci1
ata1: <ATA channel 1> on atapci1
fwohci0: <1394 Open Host Controller Interface> mem 0xde084000-0xde0847ff,0xde085000-0xde08503f irq 20 at device 13.0 on pci0
fwohci0: OHCI version 1.10 (ROM=0)
fwohci0: No. of Isochronous channels is 4.
fwohci0: EUI64 00:e0:18:00:00:b5:c2:40
fwohci0: Phy 1394a available S400, 2 ports.
fwohci0: Link S400, max_rec 2048 bytes.
firewire0: <IEEE1394(FireWire) bus> on fwohci0
fwe0: <Ethernet over FireWire> on firewire0
if_fwe0: Fake Ethernet address: 02:e0:18:b5:c2:40
fwe0: Ethernet address: 02:e0:18:b5:c2:40
fwe0: if_start running deferred for Giant
sbp0: <SBP-2/SCSI over FireWire> on firewire0
fwohci0: Initiate bus reset
fwohci0: node_id=0xc800ffc0, gen=1, CYCLEMASTER mode
firewire0: 1 nodes, maxhop <= 0, cable IRM = 0 (me)
firewire0: bus manager 0 (me)
pcib2: <ACPI PCI-PCI bridge> at device 30.0 on pci0
pci3: <ACPI PCI bus> on pcib2
pci3: <display, VGA> at device 0.0 (no driver attached)
speaker0: <PC speaker> port 0x61 on acpi0
fdc0: <floppy drive controller> port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on acpi0
fdc0: does not respond
device_attach: fdc0 attach returned 6
sio0: <16550A-compatible COM port> port 0x3f8-0x3ff irq 4 flags 0x10 on acpi0
sio0: type 16550A
sio1: <16550A-compatible COM port> port 0x2f8-0x2ff irq 3 on acpi0
sio1: type 16550A
ppc0: <ECP parallel printer port> port 0x378-0x37f,0x778-0x77b irq 7 drq 3 on acpi0
ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/16 bytes threshold
ppbus0: <Parallel port bus> on ppc0
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
fdc0: <floppy drive controller> port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on acpi0
fdc0: does not respond
device_attach: fdc0 attach returned 6
pmtimer0 on isa0
orm0: <ISA Option ROMs> at iomem 0xd0000-0xd3fff,0xd4000-0xd57ff,0xd6000-0xd6fff on isa0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
ukbd0: Unicomp Endura Keyboard, rev 1.10/1.0c, addr 2, iclass 3/1
kbd2 at ukbd0
ums0: Unicomp Endura Keyboard, rev 1.10/1.0c, addr 2, iclass 3/1
ums0: 2 buttons.
Timecounter "TSC" frequency 1746832123 Hz quality 800
Timecounters tick every 1.000 msec
ad0: 152627MB <WDC WD1600JB-00GVA0 08.02D08> at ata0-master UDMA100
acd0: DVDROM <Pioneer DVD-ROM ATAPIModel DVD-106S 0122/E1.22> at ata1-slave UDMA66
Trying to mount root from ufs:/dev/ad0s2a
Loading configuration files.
Entropy harvesting:
 interrupts
 ethernet
 point_to_point
 kickstart
.
swapon: adding /dev/ad0s2b as swap device
Starting file system checks:
/dev/ad0s2a: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ad0s2a: clean, 465865 free (1849 frags, 58002 blocks, 0.4% fragmentation)
/dev/ad0s2d: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ad0s2d: clean, 1005668 free (676 frags, 125624 blocks, 0.1% fragmentation)
/dev/ad0s2e: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ad0s2e: clean, 1013009 free (49 frags, 126620 blocks, 0.0% fragmentation)
/dev/ad0s2f: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ad0s2f: clean, 3903952 free (44440 frags, 482439 blocks, 0.9% fragmentation)
/dev/ad0s2g: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ad0s2g: clean, 62989947 free (19 frags, 7873741 blocks, 0.0% fragmentation)