Ubuntu 10.04 32bit. Udev high cpu usage when it is started also on AMD64 debian testing

[Andrius Jurkus]

Binary package hint: udev

Starting stopping udev dont help. This happened in a fresh install ubuntu 10.04 32bit same thing is in debian testing (amd64)

stoping udev cpu usage goes back to normal.

Top causes for wakeups:
   0.0% ( 0.0)D udevd
  41.2% (519.3) [ahci] <interrupt>
  35.0% (441.1) [kernel scheduler] Load balancing tick
   7.0% ( 88.6) [Rescheduling interrupts] <kernel IPI>
   1.6% ( 20.1)D firefox-bin
   2.1% ( 26.6) rhythmbox
   1.9% ( 24.5) USB device 1-2 : USB2.0-CRW (Generic)
   1.6% ( 20.2) wnck-applet
   1.5% ( 18.5) [ehci_hcd:usb1, uhci_hcd:usb5, uhci_hcd:usb7] <interrupt>
   1.2% ( 15.7) [eth0] <interrupt>
   1.0% ( 13.0) skype
   1.0% ( 12.0) pulseaudio
   0.9% ( 11.3) [extra timer interrupt]
   0.8% ( 10.0) ubuntuone-syncd
   0.6% ( 8.0) [kernel core] usb_hcd_poll_rh_status (rh_timer_func)
   0.5% ( 5.8) gkrellm
   0.4% ( 5.6) [TLB shootdowns] <kernel IPI>
   0.4% ( 5.0) syndaemon
   0.1% ( 1.6) [kernel core] timer_action (ehci_watchdog)
   0.1% ( 1.6) gnome-terminal
   0.1% ( 1.2) hald-addon-stor
   0.1% ( 1.0) [uhci_hcd:usb3, nvidia] <interrupt>

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 1507 root 20 0 15684 3108 2484 R 16 0.1 4:22.30 udisks-daemon
25264 wolas 20 0 136m 46m 28m R 13 1.2 3:17.46 nautilus
  856 messageb 20 0 3460 1996 936 R 11 0.0 3:12.93 dbus-daemon
25290 wolas 20 0 33488 3700 2816 S 6 0.1 1:03.18 gvfs-gdu-volume

strace -t -p 1507 -o strace_output

attached below

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: udev 151-12
ProcVersionSignature: Ubuntu 2.6.32-22.33-generic-pae 2.6.32.11+drm33.2
Uname: Linux 2.6.32-22-generic-pae i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Mon May 10 12:19:04 2010
ExecutablePath: /sbin/udevd
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
MachineType: Acer Aspire 6930G
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-22-generic-pae root=/dev/sda4
ProcEnviron: PATH=(custom, no user)
SourcePackage: udev
dmi.bios.date: 09/25/2008
dmi.bios.vendor: Acer
dmi.bios.version: v0.3204
dmi.board.name: Makalu
dmi.board.vendor: Acer
dmi.board.version: Not Applicable
dmi.chassis.type: 1
dmi.chassis.vendor: Acer
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnAcer:bvrv0.3204:bd09/25/2008:svnAcer:pnAspire6930G:pvrNotApplicable:rvnAcer:rnMakalu:rvrNotApplicable:cvnAcer:ct1:cvrN/A:
dmi.product.name: Aspire 6930G
dmi.product.version: Not Applicable
dmi.sys.vendor: Acer

[Andrius Jurkus (wolas)]

forget to mention this is 32 bit ubuntu version

[Andrius Jurkus (wolas)]

damn why here are not edit buton :/ i always first make 1000 mistakes then edit em :) sry for spam. And i didint saw that it automatically add version and etc... dah found it but header cant be changed?

[ariel (garcia)]

Well, i have a similar problem with a completely different setup:

Ubuntu 10.04 64bit, but on server hardware: QLogic FibreChannel adapters, with one SAN volume over multiple paths. Multipathd used to rule their access.
Udev keeps "discovering" all those SAN devices... causing a load of 3 approx.!! :-(

Not happening before with Karmic.

[Kim Yeung (kimyeung123)]

I got the same problem too

my system is
64bit ubuntu
intel G41 chipset
E2140 1.6Ghz

I have to "service udev stop" to bring my system usable again.

How can I provide more log and information for developer to follow up? I am a newbie, please provide detailed command for getting necessary log, thanks.

[Andrius Jurkus (wolas)]

Here same bug on debian http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=581791

BTW in 32bit ubuntu cpu usage is much bigger :)

[ariel (garcia)]

Ok, i could "work around" the problem in my case, by just disabling the "change" ACTION in
     /lib/udev/rules.d/95-multipath.rules
as discussed in https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/571093/comments/9

In my case, two FiberChannel adapters with access to a SAN device over 4 different paths which are then handled by multipathd, udev was constantly "discovering" the 4 multipath devices (sdb/sdc/sdd/sde) and causing a high CPU load of around 3 (8 CPU system). With "ps" i could see a process tree like this again and again:

  393 ? S<s 22:09 udevd --daemon
20696 ? S< 0:12 \_ udevd --daemon
 7171 ? S< 0:00 | \_ /sbin/multipath -v0 /dev/sdb
 7190 ? R< 0:00 | \_ /sbin/mpath_prio_emc /dev/sdd
20702 ? S< 0:10 \_ udevd --daemon
 7177 ? S< 0:00 | \_ /sbin/multipath -v0 /dev/sdc
 7189 ? R< 0:00 | \_ /lib/udev/scsi_id -g -u -d /dev/sdb
31869 ? S< 0:01 \_ udevd --daemon
 7179 ? S< 0:00 | \_ /sbin/multipath -v0 /dev/sdd
 7191 ? R< 0:00 | \_ /sbin/mpath_prio_emc /dev/sdb
31875 ? S< 0:01 \_ udevd --daemon

After having disabled the "change" ACTION in
     /lib/udev/rules.d/95-multipath.rules
the number of events got reduced from "tons per second" to one every 30 seconds in my hardware.
Thus I conclude that all the other events were spurious events generated by a udev/multipath feedback loop...

However, there is still some additional issue in the kernel/QLA-driver probably:
   the same hardware setup under Karmic doesn't trigger _any_ event in udev, not even that one every 30 seconds!

[Andrius Jurkus (wolas)]

In my system there isint such file 95-multipath.rules tried to remove everything that look suspiciaus in udev rules or said anything about cd rom. And the cpu usage is till very big i guess if i disable cdrom it will be ok since i dont use it, only for OS installs of course this is lame workaround...)

Another question stop start udev laods all that rules.d directory? no need anything else?

KERNEL[1274446496.324864] change /devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0 (scsi)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0
SUBSYSTEM=scsi
SDEV_MEDIA_CHANGE=1
DEVTYPE=scsi_device
DRIVER=sr
MODALIAS=scsi:t-0x05
SEQNUM=47783

UDEV [1274446496.333536] change /devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0 (block)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0
SUBSYSTEM=block
DEVNAME=/dev/sr0
DEVTYPE=disk
SEQNUM=47782
ID_CDROM=1
ID_CDROM_CD_R=1
ID_CDROM_CD_RW=1
ID_CDROM_DVD=1
ID_CDROM_DVD_R=1
ID_CDROM_DVD_RW=1
ID_CDROM_DVD_RAM=1
ID_CDROM_DVD_PLUS_R=1
ID_CDROM_DVD_PLUS_RW=1
ID_CDROM_DVD_PLUS_R_DL=1
ID_CDROM_MRW=1
ID_CDROM_MRW_W=1
ID_SCSI=1
ID_VENDOR=Optiarc
ID_VENDOR_ENC=Optiarc\x20
ID_MODEL=DVD_RW_AD-7560S
ID_MODEL_ENC=DVD\x20RW\x20AD-7560S\x20
ID_REVISION=SX07
ID_TYPE=cd
ID_BUS=scsi
ID_PATH=pci-0000:00:1f.2-scsi-1:0:0:0
ACL_MANAGE=1
GENERATED=1
UDISKS_PRESENTATION_NOPOLICY=0
MAJOR=11
MINOR=0
DEVLINKS=/dev/block/11:0 /dev/scd0 /dev/disk/by-path/pci-0000:00:1f.2-scsi-1:0:0:0 /dev/cdrom /dev/cdrw /dev/dvd /dev/dvdrw

[Trev Peterson (trev-advanced-reality)]

I am experiencing the same problem on the AMD64 kernel. It seems udev is continuously discovering my CD/DVD drive. Stopping udev solves the problem but this is undesirable as a long term solution.

Output of "sudo udevadm monitor --property" shows the following repeating several times per second:

KERNEL[1274866057.958054] change /devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0/block/sr0 (block)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0/block/sr0
SUBSYSTEM=block
DEVNAME=sr0
DEVTYPE=disk
SEQNUM=43253
MAJOR=11
MINOR=0

UDEV [1274866057.958095] change /devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0 (scsi)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0
SUBSYSTEM=scsi
SDEV_MEDIA_CHANGE=1
DEVTYPE=scsi_device
DRIVER=sr
MODALIAS=scsi:t-0x05
SEQNUM=43252

KERNEL[1274866057.997645] change /devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0 (scsi)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0
SUBSYSTEM=scsi
SDEV_MEDIA_CHANGE=1
DEVTYPE=scsi_device
DRIVER=sr
MODALIAS=scsi:t-0x05
SEQNUM=43254

UDEV [1274866058.035694] change /devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0/block/sr0 (block)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1f.2/host4/target4:0:0/4:0:0:0/block/sr0
SUBSYSTEM=block
DEVNAME=/dev/sr0
DEVTYPE=disk
SEQNUM=43253
ID_CDROM=1
ID_CDROM_CD_R=1
ID_CDROM_CD_RW=1
ID_CDROM_DVD=1
ID_CDROM_DVD_R=1
ID_CDROM_DVD_RW=1
ID_CDROM_DVD_RAM=1
ID_CDROM_DVD_PLUS_R=1
ID_CDROM_DVD_PLUS_RW=1
ID_CDROM_DVD_PLUS_R_DL=1
ID_CDROM_MRW=1
ID_CDROM_MRW_W=1
ID_SCSI=1
ID_VENDOR=Optiarc
ID_VENDOR_ENC=Optiarc\x20
ID_MODEL=DVD_RW_AD-7560S
ID_MODEL_ENC=DVD\x20RW\x20AD-7560S\x20
ID_REVISION=SX01
ID_TYPE=cd
ID_BUS=scsi
ID_PATH=pci-0000:00:1f.2-scsi-4:0:0:0
ACL_MANAGE=1
GENERATED=1
UDISKS_PRESENTATION_NOPOLICY=0
MAJOR=11
MINOR=0
DEVLINKS=/dev/block/11:0 /dev/scd0 /dev/disk/by-path/pci-0000:00:1f.2-scsi-4:0:0:0 /dev/cdrom /dev/cdrw /dev/dvd /dev/dvdrw

[Phuah Yee Keat (ykphuah)]

Affects me, running 10.04 64bit

[taolab (marco-demichele-taolab)]

It may be a DMA problem. In my case (Ubuntu 32bit 10.04 - Optiarc Dvd Rom) changing BIOS configuration for DVD Rom to MWDMA2 instead of AUTO (UDMA5) problem disappeared.

[taolab (marco-demichele-taolab)]

Nothing! The problem is still present, It disappeared using a DVD disc (I don't know why?) different from the others DVD discs used till now.