gentoo-live ~ # mount|grep udev udev on /dev type tmpfs (rw,nosuid,relatime,size=10240k,mode=755) cloc3@s939 ~ $ mount|grep udev udev on /dev type tmpfs (rw,nosuid,relatime,size=10240k,mode=755) size=10240k. why? I'm using sys-fs/udev-146-r1 Reproducible: Always Steps to Reproduce: 1. just using udev with default configuration. Expected Results: size=1024k s939 busy # emerge --info Portage 2.1.7.4 (default/linux/amd64/10.0/desktop, gcc-4.4.2, glibc-2.10.1-r0, 2.6.30-gentoo-r6-p5q x86_64) ================================================================= System uname: Linux-2.6.30-gentoo-r6-p5q-x86_64-Intel-R-_Core-TM-2_Quad_CPU_Q9400_@_2.66GHz-with-gentoo-2.0.1 Timestamp of tree: Tue, 10 Nov 2009 20:00:01 +0000 distcc 3.1 x86_64-pc-linux-gnu [disabled] app-shells/bash: 4.0_p28 dev-java/java-config: 2.1.9-r1 dev-lang/python: 2.6.2-r1 dev-python/pycrypto: 2.0.1-r8 dev-util/cmake: 2.6.4-r3 sys-apps/baselayout: 2.0.1 sys-apps/openrc: 0.5.2-r1 sys-apps/sandbox: 2.2 sys-devel/autoconf: 2.13, 2.63-r1 sys-devel/automake: 1.7.9-r1, 1.8.5-r3, 1.9.6-r2, 1.10.2, 1.11 sys-devel/binutils: 2.20 sys-devel/gcc-config: 1.4.1 sys-devel/libtool: 2.2.6a virtual/os-headers: 2.6.27-r2 ACCEPT_KEYWORDS="amd64" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=native -O2 -pipe -fomit-frame-pointer" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/share/X11/xkb /usr/share/config /var/spool/torque" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/env.d/java/ /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/php/apache2-php5/ext-active/ /etc/php/cgi-php5/ext-active/ /etc/php/cli-php5/ext-active/ /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 /etc/udev/rules.d" CXXFLAGS="-march=native -O2 -pipe -fomit-frame-pointer" DISTDIR="/var/gentoo-var/distfiles" FEATURES="assume-digests buildpkg distlocks fixpackages news parallel-fetch protect-owned sandbox sfperms strict unmerge-logs unmerge-orphans userfetch" GENTOO_MIRRORS="http://gentoo.mneisen.org/ http://gentoo.wheel.sk/ http://gentoo.mirror.pw.edu.pl/ http://gentoo.tiscali.nl/ http://gentoo.virginmedia.com/" LC_ALL="it_IT.UTF-8" LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,--hash-style=gnu" LINGUAS="it en_GB" MAKEOPTS="-j9 -s" PKGDIR="/var/gentoo-var/packages64" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/var/gentoo-var/portage" PORTDIR_OVERLAY="/usr/portage/local/layman/gechi /usr/local/portage" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="3dnow 3dnowext X a52 aac aalib acl acpi alsa amd64 ao aotuv apache2 asf asyncns audiofile avi bash-completion beagle berkdb bitmap-fonts bluetooth branding browserplugin bzip2 bzlib cairo caps cdda cddb cdparanoia cdr chroot cli coverage cpdflib cpudetection cracklib crypt cspell cups cupsddk curl dba dbus dga directfb divx djvu dlloader dmi dri dts dv dvd dvdr dvdread dvx4linux eds emboss encode esd evo exif expat fam fbcon ffmpeg flac foomaticdb fortran fpx ftp gcj gd gdbm ggvorbis gif gimp glitz gmedia gmp gnome gphoto2 gpm graphviz gstreamer gtk gtkhtml hal htmlhandbook iconv idn ieee1394 imagemagick imlib innodb jack java javascript jbig jikes jpeg jpeg2k kde kdeenablefinal kdehiddenvisibility kdexdeltas kerberos kipi ladspa lame lcms ldap libcaca libnotify libsamplerate live lm_sensors lzo mad madwifi mailwrapper md5sum memlimit mikmod mime mjpeg mmap mmx mng modules motif mozilla mp3 mp4 mpeg mpi mplayer mssql mudflap multilib mysql nas ncurses network newspr nls nptl nptlonly nsplugin ntlm nuv nvidia ogg openexr opengl openmp oss pam pam_chroot pam_timestamp pango pcmcia pcre pdf perl phonon php plasma png policykit portaudio posix ppds pppd pulseaudio pwdb python qt3support qt4 quicktime readline reflection rle rtc samba sasl scanner sdl seamonkey session slang sndfile snmp sox speex spell spl sse sse2 ssl startup-notification svg sysfs tcltk tcpd tetex tga theora threads thunar tidy tiff tokenizer tools trace truetype truetype-fonts type1-fonts udev unicode urandom usb userlocales utempter vcd vim-syntax vnc vorbis webkit wmf wmp x264 xattr xcb xcomposite xine xinerama xml xml2 xmlreader xmlwriter xmms xorg xpm xslt xv xvid xvmc zlib" 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="actions alias auth_basic auth_digest authn_anon authn_dbd authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache dav dav_fs dav_lock dbd deflate dir disk_cache env expires ext_filter file_cache filter headers ident imagemap include info log_config logio mem_cache mime mime_magic negotiation proxy proxy_ajp proxy_balancer proxy_connect proxy_http rewrite setenvif so speling status unique_id userdir usertrack vhost_alias" ELIBC="glibc" INPUT_DEVICES="keyboard mouse evdev void" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LINGUAS="it en_GB" USERLAND="GNU" VIDEO_CARDS="nouveau nvidia vesa nv vga vmware" Unset: CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, FFLAGS, INSTALL_MASK, LANG, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS
The mount option is there to limit the space /dev can use. By default tmpfs is limited to use a maximum of 50% of available ram. So udev uses size=10M to limit this to a sane value. mount just displays it in kB. If you want to change this, you can add an entry for /dev to your /etc/fstab and it is automatically used instead of this hardcoded entry. from /etc/init.d/udev-mount: # mount -n -t tmpfs -o "exec,nosuid,mode=0755,size=10M" udev /dev
ok. I've understood. in my system: s939 ~ # du -sh /dev/ 524K /dev/ so, I think may it be better a lower value. if you like, set solved this bug.
A lower value may be possible, but we cannot guess how udev behaves on larger systems, as its database is also stored in /dev/.udev. I think 10MB is fine as an upper limit. So far there were no complaint it is too low. And loosing 10M if some processes try to fill it up completely should not getting the system out of memory.
