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The storage of the unit objects on the heap is currently not very efficient. For every unit object we allocate a chunk of memory as large as the biggest unit type, although there are significant differences in the units' real requirements. pahole shows the following sizes of structs: 488 Target 496 Snapshot 512 Device 528 Path 560 Timer 576 Automount 1080 Socket 1160 Swap 1168 Service 1280 Mount Usually there aren't many targets or snapshots in the system, but Device is one of the most common unit types and for every one we waste 1280 - 512 = 768 bytes. Fix it by allocating only the right amount for the given unit type. On my machine (x86_64, with 39 LVM volumes) this decreases systemd's USS (unique set size) by more than 300 KB. |
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| m4 | ||
| man | ||
| po | ||
| src | ||
| sysctl.d | ||
| test | ||
| tmpfiles.d | ||
| units | ||
| .dir-locals.el | ||
| .gitignore | ||
| .mailmap | ||
| autogen.sh | ||
| CODING_STYLE | ||
| configure.ac | ||
| DISTRO_PORTING | ||
| introspect.awk | ||
| LICENSE | ||
| Makefile.am | ||
| README | ||
| TODO | ||
systemd System and Session Manager
DETAILS:
http://0pointer.de/blog/projects/systemd.html
WEB SITE:
http://www.freedesktop.org/wiki/Software/systemd
GIT:
git://anongit.freedesktop.org/systemd
ssh://git.freedesktop.org/git/systemd
GITWEB:
http://cgit.freedesktop.org/systemd/
MAILING LIST:
http://lists.freedesktop.org/mailman/listinfo/systemd-devel
http://lists.freedesktop.org/mailman/listinfo/systemd-commits
IRC:
#systemd on irc.freenode.org
BUG REPORTS:
https://bugs.freedesktop.org/enter_bug.cgi?product=systemd
AUTHOR:
Lennart Poettering with major support from Kay Sievers
LICENSE:
GPLv2+ for all code, except sd-daemon.[ch] and
sd-readahead.[ch] which are MIT
REQUIREMENTS:
Linux kernel >= 2.6.39
with devtmpfs
with cgroups (but it's OK to disable all controllers)
optional but strongly recommended: autofs4, ipv6
libudev >= 172
dbus >= 1.4.0
libcap
gtk+ >= 2.20 (optional)
PAM >= 1.1.2 (optional)
libcryptsetup (optional)
libaudit (optional)
libselinux (optional)
tcpwrappers (optional)
libnotify (optional)
When you build from git you need the following additional dependencies:
vala >= 0.10
docbook-xsl
xsltproc
automake
autoconf
libtool
gperf
make, gcc, and similar tools
During runtime you need the following dependencies:
util-linux > v2.18 (requires fsck -l, agetty -s)
sulogin (from sysvinit-tools, optional but recommended)
plymouth (optional)
dracut (optional)
When systemd-hostnamed is used it is strongly recommended to
install nss-myhostname to ensure that in a world of
dynamically changing hostnames the hostname stays resolveable
under all circumstances. In fact, systemd-hostnamed will warn
if nss-myhostname is not installed. Packagers are encouraged to
add a dependency on nss-myhostname to the package that
includes systemd-hostnamed.
Note that D-Bus can link against libsystemd-login.so, which
results in a cyclic build dependency. To accomodate for this
please build D-Bus without systemd first, then build systemd,
then rebuild D-Bus with systemd support.
WARNINGS:
systemd will warn you during boot if /etc/mtab is not a
symlink to /proc/mounts. Please ensure that /etc/mtab is a
proper symlink.
systemd will warn you during boot if /usr is on a different
file system than /. While in systemd itself very little will
break if /usr is on a separate partition many of its
dependencies very likely will break sooner or later in one
form or another. For example udev rules tend to refer to
binaries in /usr, binaries that link to libraries in /usr or
binaries that refer to data files in /usr. Since these
breakages are not always directly visible systemd will warn
about this, since this kind of file system setup is not really
supported anymore by the basic set of Linux OS components.
For more information on this issue consult
http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken
ENGINEERING AND CONSULTING SERVICES:
ProFUSION <http://profusion.mobi> offers professional
engineering and consulting services for systemd for embedded
and other use. Please contact Gustavo Barbieri
<barbieri@profusion.mobi> for more information.
Disclaimer: This notice is not a recommendation or official
endorsement. However, ProFUSION's upstream work has been very
beneficial for the systemd project.