Bug 457732 – kde-base/kwin - Hyperthreading enabled + Java = Kwin unresponsive

• Product: Gentoo Linux
• Status: RESOLVED NEEDINFO

[Description Till Schäfer 2013-02-15 17:14:18 UTC]

When enabling Hyperthreading and runnning a CPU intensive task in java kwin becomes unresponsive (not reacting to input for several seconds to minutes).

using top form a terminal shows the following picture: 

  PID USER     PR  NI  VIRT  RES  SHR S %CPU %MEM  TIME+    COMMAND 
31385 schaefer 39  19 7113m 5.1g  11m S  651 33.2  3883:13  java                                  
27764 schaefer 10 -10 1029m 198m  42m R   99  1.3  21:14.00 kwin

Kwin stays at 100% CPU all the time. When disabling Hyperthreading by setting the HT cores to offline over the sysfs, the system becomes responsive again.

An interesting observation is that this phenomena does not appear when compiling c++ code oder using emerge. However the java process is different, because it stays alive a very long time and does not have many small tasks.

This may be a scheduling problem in the kernel, but i am unsure about that and i am reporting to gentoo bugtracker first. 

Reproducible: Sometimes

Steps to Reproduce:
1.run kde (i am running 4.10)
2. run java application which uses all cores (including HT cores)
3.watch kwin CPU utilization 



emerge --info
Portage 2.2.0_alpha163 (default/linux/amd64/13.0/desktop/kde, gcc-4.6.3, glibc-2.15-r3, 3.6.11-gentoo x86_64)
=================================================================
System uname: Linux-3.6.11-gentoo-x86_64-Intel-R-_Core-TM-_i7-3770_CPU_@_3.40GHz-with-gentoo-2.1
KiB Mem:    15990200 total,    754596 free
KiB Swap:   16801788 total,  16757076 free
Timestamp of tree: Fri, 15 Feb 2013 10:00:01 +0000
ld GNU ld (GNU Binutils) 2.22
ccache version 3.1.8 [disabled]
app-shells/bash:          4.2_p37
dev-java/java-config:     2.1.12-r1
dev-lang/python:          2.7.3-r2, 3.2.3
dev-util/ccache:          3.1.8
dev-util/cmake:           2.8.9
dev-util/pkgconfig:       0.28
sys-apps/baselayout:      2.1-r1
sys-apps/openrc:          0.11.8
sys-apps/sandbox:         2.5
sys-devel/autoconf:       2.13, 2.69
sys-devel/automake:       1.11.6
sys-devel/binutils:       2.22-r1
sys-devel/gcc:            4.6.3
sys-devel/gcc-config:     1.7.3
sys-devel/libtool:        2.4-r1
sys-devel/make:           3.82-r4
sys-kernel/linux-headers: 3.6 (virtual/os-headers)
sys-libs/glibc:           2.15-r3
Repositories: gentoo local_overlay
Installed sets: @kdeartwork-4.8, @kdebase-4.8, @system
ACCEPT_KEYWORDS="amd64"
ACCEPT_LICENSE="*"
CBUILD="x86_64-pc-linux-gnu"
CFLAGS="-march=native -O2 -pipe -ggdb"
CHOST="x86_64-pc-linux-gnu"
CONFIG_PROTECT="/etc /usr/share/config /usr/share/gnupg/qualified.txt /var/lib/hsqldb"
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 /etc/texmf/language.dat.d /etc/texmf/language.def.d /etc/texmf/updmap.d /etc/texmf/web2c"
CXXFLAGS="-march=native -O2 -pipe -ggdb"
DISTDIR="/usr/portage/distfiles"
EMERGE_DEFAULT_OPTS="--with-bdeps=y --autounmask-write --jobs --load-average=10.0"
FCFLAGS="-O2 -pipe"
FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch parallel-install preserve-libs protect-owned sandbox sfperms splitdebug strict unknown-features-warn unmerge-logs unmerge-orphans userfetch"
FFLAGS="-O2 -pipe"
GENTOO_MIRRORS="http://distfiles.gentoo.org"
LANG="en_US.utf8"
LDFLAGS="-Wl,-O1 -Wl,--as-needed"
MAKEOPTS="-j9"
PKGDIR="/usr/portage/packages"
PORTAGE_BZIP2_COMMAND="/usr/bin/pbzip2"
PORTAGE_CONFIGROOT="/"
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY="/usr/local/portage"
SYNC="rsync://rsync.gentoo.org/gentoo-portage"
USE="64bit X a52 aac acl acpi alsa amd64 bash-completion berkdb bluetooth branding bzip2 cairo cdaudio cdda cddb cdio cdr cli consolekit cracklib crypt css cups cxx dbus declarative dell dri dts dvd dvdr emboss encode exif fam ffmpeg firefox flac fortran gdbm gif glib glibc gpm gtk haskell iconv icu id3tag ieee1394 imagemagick inotify ipv4 ipv6 irc java jpeg jpeg2k kde kipi lame latex lcms ldap libnotify libsamplerate lzma mad mmx mmxext mng modules mp3 mp4 mpeg mplayer mudflap multilib musicbrainz ncurses nls nptl ntp ogg okteta opengl openmp otr pam pango pcre pdf phonon plasma pm-utils png policykit ppds pulseaudio qemu qt3support qt4 quicktime rar readline rss sdl semantic-desktop session spell spice sse sse2 sse3 sse4 sse4_1 ssl ssse3 startup-notification svg syslog taglib tcpd threads tiff truetype udev udisks unicode upower usb v41 v412 v4l vaapi vcd vim-syntax visualization vorbis wavpack wifi wma wmf wxwidgets x264 xcb xcomposite xine xinerama xml xscreensaver xv xvid xvmc 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" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mmap_emul mulaw multi null plug rate route share shm softvol" 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" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" 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 ubx" GRUB_PLATFORMS="efi-64" 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" LINGUAS="de" PHP_TARGETS="php5-3" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7 python3_2" QEMU_SOFTMMU_TARGETS="i386 x86_64" QEMU_USER_TARGETS="i386 x86_64" RUBY_TARGETS="ruby18 ruby19" USERLAND="GNU" VIDEO_CARDS="intel" 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:  CPPFLAGS, CTARGET, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, USE_PYTHON

[Comment 1 Till Schäfer 2013-02-15 17:15:07 UTC]

Created attachment 338998 [details]
Kernel config

[Comment 2 Till Schäfer 2013-02-15 17:16:22 UTC]

forget to mention that i am using dev-java/icedtea-6.1.12.2

[Comment 3 Johannes Huber (RETIRED) 2013-07-05 19:55:08 UTC]

I would suggest to you for reporting this upstream, or is this already fixed for you?

[Comment 4 Till Schäfer 2013-07-12 15:20:15 UTC]

i currently do not have the time to test this again, but i will put this on my todo list and do so later.

[Comment 5 Till Schäfer 2013-09-04 14:13:06 UTC]

i don't have the time to dig into this. So you may want to close this bug.

[Comment 6 Michael Palimaka (kensington) 2013-09-04 14:14:13 UTC]

Thank-you for taking the time to follow up an anyway, it's much appreciated.