Bug 567154

Summary:	systemd-udevd high CPU usage in Hyper-V VM
Product:	Gentoo Linux	Reporter:	Jernej Simončič <jernej-bugzilla.gentoo2>
Component:	[OLD] Core system	Assignee:	Gentoo Kernel Bug Wranglers and Kernel Maintainers <kernel>
Status:	RESOLVED NEEDINFO
Severity:	normal	CC:	floppym, udev-bugs
Priority:	Normal
Version:	unspecified
Hardware:	AMD64
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Jernej Simončič 2015-11-30 10:21:38 UTC

I have a Gentoo VM running on Hyper-V Server 2012 (not R2), and noticed that systemd-udevd is using about 50% CPU (the VM is configured with a single core, and I don't have access to the host).

udevadm monitor shows a lot of
KERNEL[476027.528506] add      /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585159 (vmbus)
KERNEL[476027.528711] add      /devices/virtual/misc/vmbus!hv_vss (misc)
UDEV  [476027.529214] add      /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585159 (vmbus)
UDEV  [476027.529509] add      /devices/virtual/misc/vmbus!hv_vss (misc)
KERNEL[476027.529905] remove   /devices/virtual/misc/vmbus!hv_vss (misc)
KERNEL[476027.529983] remove   /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585159 (vmbus)
UDEV  [476027.530487] remove   /devices/virtual/misc/vmbus!hv_vss (misc)
UDEV  [476027.530929] remove   /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585159 (vmbus)
KERNEL[476027.531131] add      /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585160 (vmbus)
KERNEL[476027.531198] add      /devices/virtual/misc/vmbus!hv_vss (misc)
UDEV  [476027.531842] add      /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585160 (vmbus)
KERNEL[476027.532281] remove   /devices/virtual/misc/vmbus!hv_vss (misc)
KERNEL[476027.532354] remove   /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585160 (vmbus)
UDEV  [476027.532524] add      /devices/virtual/misc/vmbus!hv_vss (misc)
UDEV  [476027.532979] remove   /devices/virtual/misc/vmbus!hv_vss (misc)
UDEV  [476027.533391] remove   /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585160 (vmbus)
KERNEL[476027.536106] add      /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585161 (vmbus)
KERNEL[476027.536176] add      /devices/virtual/misc/vmbus!hv_vss (misc)
UDEV  [476027.536867] add      /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/vmbus_155585161 (vmbus)

I have found a similar bug report at launchpad, so this probably isn't Gentoo-specific:
<https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1496927>

Reproducible: Always

Steps to Reproduce:
1. Boot Gentoo with recent kernel on Hyper-V 2012




Portage 2.2.20.1 (python 3.4.3-final-0, default/linux/amd64/13.0/no-multilib, gcc-4.9.3, glibc-2.21-r1, 4.3.0-gentoo x86_64)
=================================================================
System uname: Linux-4.3.0-gentoo-x86_64-Intel-R-_Xeon-R-_CPU_X6550_@_2.00GHz-with-gentoo-2.2
KiB Mem:     2054828 total,    415824 free
KiB Swap:    2097148 total,   2097148 free
Timestamp of repository gentoo: Mon, 30 Nov 2015 00:30:01 +0000
sh bash 4.3_p39
ld GNU ld (Gentoo 2.25.1 p1.1) 2.25.1
app-shells/bash:          4.3_p39::gentoo
dev-lang/perl:            5.20.2::gentoo
dev-lang/python:          2.7.10-r1::gentoo, 3.4.3::gentoo
dev-util/cmake:           3.3.1-r1::gentoo
dev-util/pkgconfig:       0.28-r2::gentoo
sys-apps/baselayout:      2.2::gentoo
sys-apps/openrc:          0.17::gentoo
sys-apps/sandbox:         2.6-r1::gentoo
sys-devel/autoconf:       2.69::gentoo
sys-devel/automake:       1.14.1::gentoo, 1.15::gentoo
sys-devel/binutils:       2.25.1-r1::gentoo
sys-devel/gcc:            4.9.3::gentoo
sys-devel/gcc-config:     1.7.3::gentoo
sys-devel/libtool:        2.4.6::gentoo
sys-devel/make:           4.1-r1::gentoo
sys-kernel/linux-headers: 3.18::gentoo (virtual/os-headers)
sys-libs/glibc:           2.21-r1::gentoo
Repositories:

gentoo
    location: /usr/portage
    sync-type: rsync
    sync-uri: rsync://rsync.gentoo.org/gentoo-portage
    priority: -1000

ACCEPT_KEYWORDS="amd64"
ACCEPT_LICENSE="* -@EULA"
CBUILD="x86_64-pc-linux-gnu"
CFLAGS="-O2 -pipe"
CHOST="x86_64-pc-linux-gnu"
CONFIG_PROTECT="/etc /etc/stunnel/stunnel.conf /usr/share/easy-rsa /var/bind"
CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo"
CXXFLAGS="-O2 -pipe"
DISTDIR="/usr/portage/distfiles"
FCFLAGS="-O2 -pipe"
FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync xattr"
FFLAGS="-O2 -pipe"
GENTOO_MIRRORS="http://distfiles.gentoo.org"
LANG="sl_SI"
LC_ALL="sl_SI.UTF-8"
LDFLAGS="-Wl,-O1 -Wl,--as-needed"
MAKEOPTS="-j2"
PKGDIR="/usr/portage/packages"
PORTAGE_CONFIGROOT="/"
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages"
PORTAGE_TMPDIR="/var/tmp"
USE="acl ads amd64 berkdb bindist bzip2 cli cracklib crypt cups cxx dri fortran gdbm iconv ipv6 mmx mmxext modules ncurses nls nptl offensive openmp pam pcre python readline seccomp session sse sse2 sse3 ssl ssse3 tcpd unicode xattr zlib" ABI_X86="64" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" CPU_FLAGS_X86="mmx sse sse2 sse3 ssse3" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ublox ubx" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-5" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7 python3_4" RUBY_TARGETS="ruby20 ruby21" USERLAND="GNU" VIDEO_CARDS="fbdev glint intel mach64 mga nouveau nv r128 radeon savage sis tdfx trident vesa via vmware dummy v4l" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account"
Unset:  CC, CPPFLAGS, CTARGET, CXX, EMERGE_DEFAULT_OPTS, INSTALL_MASK, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, USE_PYTHON

Comment 1 Mike Gilbert gentoo-dev

2015-11-30 15:56:39 UTC

Sounds like a kernel problem to me; it seems to be spamming device add events.

In any case, what version of systemd/udev are you running?

Comment 2 Jernej Simončič 2015-11-30 17:13:00 UTC

I'm running udev-216 with openrc-0.17.

Comment 3 Alice Ferrazzi Gentoo Infrastructure

2017-04-29 15:49:23 UTC

is this still a problem ?