I just rebooted my G5 a moment ago, and on reboot, the new glibc-2.7 nscd was started. At that exact point, everything slowed down a complete goop. Took 10 minutes from then to finish the boot, that normally takes 5 seconds. ran top (again painfully slow to load), and nscd was at the top, taking ALL cputime. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 7450 root 20 0 130m 1280 836 S 400 0.0 53:42.20 nscd This machine does not use any network based services, just local ones. nsswitch.conf: passwd: compat shadow: compat group: compat hosts: files dns networks: files dns services: db files protocols: db files rpc: db files ethers: db files netmasks: files netgroup: files bootparams: files automount: files aliases: files # emerge --info Portage 2.1.3.19 (default-linux/ppc/ppc64/2007.1/32bit-userland/desktop/970/pmac, gcc-4.2.2, glibc-2.7-r0, 2.6.23-gentoo-r1-prod ppc64) ================================================================= System uname: 2.6.23-gentoo-r1-prod ppc64 PPC970MP, altivec supported Timestamp of tree: Tue, 23 Oct 2007 17:00:01 +0000 ccache version 2.4 [enabled] app-shells/bash: 3.2_p17-r1 dev-lang/python: 2.5.1-r3 dev-python/pycrypto: 2.0.1-r6 dev-util/ccache: 2.4-r7 sys-apps/baselayout: 1.12.10-r5 sys-apps/sandbox: 1.2.18.1-r2 sys-devel/autoconf: 2.13, 2.61-r1 sys-devel/automake: 1.5, 1.6.3, 1.7.9-r1, 1.8.5-r3, 1.9.6-r2, 1.10 sys-devel/binutils: 2.18-r1 sys-devel/gcc-config: 1.4.0-r4 sys-devel/libtool: 1.5.24 virtual/os-headers: 2.6.23-r1 ACCEPT_KEYWORDS="ppc ~ppc" CBUILD="powerpc-unknown-linux-gnu" CFLAGS="-pipe -O2 -mtune=970 -mcpu=970 -mabi=altivec" CHOST="powerpc-unknown-linux-gnu" CONFIG_PROTECT="/etc /usr/kde/3.5/env /usr/kde/3.5/share/config /usr/kde/3.5/shutdown /usr/share/config" CONFIG_PROTECT_MASK="/etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/revdep-rebuild /etc/terminfo /etc/texmf/web2c /etc/udev/rules.d" CXXFLAGS="-pipe -O2 -mtune=970 -mcpu=970 -mabi=altivec" DISTDIR="/home/gentoo/distfiles" FEATURES="autoconfig buildpkg ccache collision-protect distlocks lmirror metadata-transfer mirror parallel-fetch sandbox sfperms splitdebug strict unmerge-orphans userfetch" GENTOO_MIRRORS="http://distfiles.gentoo.org http://distro.ibiblio.org/pub/linux/distributions/gentoo" LINGUAS="af en en_GB en_ZA" MAKEOPTS="-j7" PKGDIR="/home/gentoo/packages/buck-int-2007.1/ppc64-32ul/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --delete-after --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --filter=H_**/files/digest-*" PORTAGE_TMPDIR="/dev/shm" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/code/gentoo/gentoo-cvs/gentoo-x86" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="X aac acl adplug alsa altivec ares arts audiofile avahi bash-completion berkdb bitmap-fonts bluetooth bzip2 cairo cddb cdr chardet cli cracklib crypt cscope cups curl dbus diskio dri dvd dvdr eds emboss emf encode esd expat fam fftw firefox flac fortran gcc64 gd gdbm gif gmp gnokii gnome gnutls gstreamer gtk hal ical iconv ieee1394 imagemagick imlib ipv6 isdnlog javacomm jbig jpeg jpeg2k kde latex ldap libsamplerate logitech-mouse mad midi mikmod mmap modplug mp3 mpeg mudflap musepack ncurses nls nptl nptlonly offensive ogg openexr opengl openmp oss pam pcre pda pdf perl plotutils png povray ppc pppd pulseaudio python qt3 qt3support qt4 quicktime readline reflection rpc scanner sdl session sid slp smp sms smux sndfile snmp socks5 solver speex spell spl ssl svg sysfs tcpd tetex theora tidy tiff timidity truetype truetype-fonts tta type1-fonts unicode urandom usb v4l vim-syntax vorbis vorbis-psy wavpack wideband wifi wma wmf xcb xcomposite xinerama xinetd xml xorg xscreensaver xv zlib" ALSA_CARDS="aoa aoa-fabric-layout aoa-onyx aoa-soundbus aoa-soundbus-i2s aoa-tas aoa-toonie" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mulaw multi null plug rate route share shm softvol" ELIBC="glibc" FOO2ZJS_DEVICES="hp1020" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LINGUAS="af en en_GB en_ZA" USERLAND="GNU" VIDEO_CARDS="dummy fbdev nv none radeon avivo radeonhd" Unset: CTARGET, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LANG, LC_ALL, LDFLAGS, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS
after stopping nscd, and restarting it, it takes hardly any CPU, but then if you do ~100 lookups on different entries, it will go back to lots of CPU usage. restarting it keeps the cache, so you need to do a different lookup. I enabled nscd debugging, and got this from the /var/log/nscd.log: 12047: considering GETPWBYNAME entry "", timeout 0 Repeating infinitely. I then disabled caching of passwd, and repeated the test. This time it only went to 100% cpu, with the following in the log: 12722: pruning hosts cache; time 1194931343 12722: pruning hosts cache; time 1194931358 12722: pruning hosts cache; time 1194931373 12722: pruning hosts cache; time 1194931388 12722: pruning hosts cache; time 1194931403
nscd is part of glibc
@Robin If you still have this issue you may try the diff from bug 202055. Maybe it helps.
that bug doesnt have anything to do with this one ... that is about CFI unwinding in the clone function on *x86 and amd64*. nscd is not involved in unwinding. i can reproduce on my ppc but not my amd64 ... while i cant make it happen instantly, if i just leave it for ~30 seconds, it starts eating my procs
Today I was hit by same problem. My system starts to crawl after bootup and it was nscd :/ Funny I use it for quite long time now without any problem. Pegasos G4 1GHz, 2.6.23.9, glibc 2.7-r1
please retest with glibc-2.8
appears to be fixed with glibc-2.8 on my ppc
